Twin Disc: Service Manual [PDF]

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TWIN DISC INCORPORATED



Service Manual Power Take-off Model: SP-218 Series SP-318 Series SP-318SB Series SP-321 Series



Document Number: 1022764



NOTICE Twin Disc, Incorporated makes no warranty or guaranty of any kind, expressed, implied or otherwise, with regard to the information contained within this manual. Twin Disc, Incorporated has developed this manual through research and testing of the information contained therein. Twin Disc, Incorporated assumes no responsibility for any errors that may appear in this manual and shall not be liable under any circumstances for incidental, consequential or punitive damages in connection with, or arising out of, the use of this manual. The information contained within this manual is subject to change without notice.



Document Number 1022764



Issued January, 2008



Power Take-off Service Manual



REVISION AND REISSUE DATA Issued



January, 2008



BEFORE YOU START This manual replaces: #1016062 for use with model SP218OP Series, #1016063 for use with model SP318P Series, #1016064 for use with model SP321P Series, #1016992 for use with model SP318SB Series, #1017533 for use with model SP318IL Series.



LIMITED TWIN DISC GENERAL WARRANTY, LIMITATIONS OF REMEDIES AND LIMITATION OF OTHER WARRANTIES A.



Twin Disc, Incorporated warrants all assembled products and parts (except component products or parts on which written warranties are issued by the respective manufacturers thereof and are furnished to the original customer, as to which Twin Disc, Incorporated makes no warranty and assumes no liability) against defective materials or workmanship. For products and parts other than Rockford power take-offs, such warranty shall extend for a period of twenty-four (24) months from the date of original shipment by Twin Disc, Incorporated to the original customer, but not to exceed twelve (12) months of service or two thousand (2,000) hours of service, whichever occurs first. This is the only warranty made by Twin Disc, Incorporated and is in lieu of any and all other warranties, express or implied, including the warranties of merchantability and fitness for a particular purpose and no other warranties are implied or intended to be given by Twin Disc, Incorporated. The original customer does not rely upon any tests or inspections by Twin Disc, Incorporated or on Twin Disc, Incorporated's application engineering.



B.



In consideration of the Limited Twin Disc General Warranty (hereafter called warranty) and price Twin Disc, Incorporated charges (which reflects Twin Disc, Incorporated's limited liability), the exclusive remedy provided by Twin Disc, Incorporated whether arising out of warranty within the applicable warranty period as specified, or otherwise (including tort liability), shall at the sole option of Twin Disc, Incorporated be either the repair or replacement of any Twin Disc, Incorporated part or product found by Twin Disc, Incorporated to be defective (or equivalent credit). Under no circumstances, including a failure of the exclusive remedy, shall Twin Disc, Incorporated be liable for economic loss, consequential, punitive or incidental damages. The above warranty and remedy are subject to the following terms and conditions: 1.



Complete parts or products upon request must be returned transportation prepaid and also the claims submitted to Twin Disc, Incorporated within sixty (60) days after completion of the in warranty repair. 2. The warranty is void if, in the opinion of Twin Disc, Incorporated, the failure of the part or product resulted from abuse, neglect, improper maintenance or accident. 3. The warranty is void if any modifications are made to any product or part without the prior written consent of Twin Disc, Incorporated. 4. The warranty is void unless the product or part is properly transported, stored and cared for from the date of shipment to the date placed in service. 5. The warranty is void unless the product or part is properly installed and maintained within the rated capacity of the product or part with installations properly engineered and in accordance with the practices, methods and instructions approved or provided by Twin Disc, Incorporated. 6. The warranty is void unless all required replacement parts or products are of Twin Disc origin or are Twin Disc authorized replacement parts, and otherwise identical with components of the original equipment. Replacement parts or products not of Twin Disc origin are not warranted by Twin Disc, Incorporated. C. As consideration for this warranty, the original customer and subsequent purchaser agree to indemnify and hold Twin Disc, Incorporated harmless from and against all and any loss, liability, damages or expenses for injury to persons or property, including without limitation, the original customer's and subsequent purchaser's employees and property, due to their acts or omissions or the acts or omissions of their agents, and employees in the installation, transportation, maintenance, use and operation of said equipment. D.



Only a Twin Disc, Incorporated authorized factory representative shall have authority to assume any cost or expense in the service, repair or replacement of any part or product within the warranty period, except when such cost or expense is authorized in advance in writing by Twin Disc, Incorporated.



E.



Twin Disc, Incorporated reserves the right to improve the product through changes in design or materials without being obligated to incorporate such changes in products of prior manufacture. The original customer and subsequent purchasers will not use any such changes as evidence of insufficiency or inadequacy of prior designs or materials.



F.



If failure occurs within the warranty period, and constitutes a breach of warranty, repair or replacement parts will be furnished on a no charge basis and these parts will be covered by the remainder of the unexpired warranty which remains in effect on the complete unit.



*Note The Above constitutes the basic Twin Disc, Incorporated General Limited Warranty and may be supplemented by additional published warranty terms dependent upon the product involved. Supplementary warranty terms are available upon request.



December 14, 2007



TDWP0001 rev 2008



NOTES



Twin Disc, Incorporated



Table of Contents



Table of Contents Introduction .......................................................... 11 General Information ............................................................................ 11 Replacement Parts .............................................................................. 12 Preventive Maintenance/Troubleshooting......................................... 13 Safety ................................................................................................... 14 Sources of Service Information ......................................................... 15 Warranty .............................................................................................. 16



Description and Specifications ...........................17 General Information ............................................................................ 17 Identifying the Twin Disc Power Take-Off Model Number ................ 18 Identifying the Twin Disc Power Take-off Model ............................... 19 Twin Disc Power Take-Off Reference Listing .................................... 20 Twin Disc Power Take-Off Reference Listing .................................... 21 Identifying the SAE Housing Size ...................................................... 22 Specifications ...................................................................................... 23 Twin Disc PTO Support Plate Specifications .................................... 27 Wear Limits.......................................................................................... 28 Torque Values for Fasteners .............................................................. 32



Installation ............................................................35 Installation Tips ................................................................................... 35 Prior to Installation (Ref: SAE J1033 and J617) ................................ 40 Drive Ring Installation ........................................................................ 44 Ball-Type Pilot Bearing Installation .................................................... 45 Roller-Type Pilot Bearing Installation ................................................ 46 PTO Installation to Engine or Driving Member ................................. 48 Hand Lever Position for Twin Disc Power Take-Offs ........................ 52 Position and Measure Alignment of the Sheave ............................... 53 Allowable Side Loads ......................................................................... 54 Alignment - U-Joint-Type Installation ................................................ 64 Setting Up Air Engagement on Twin Disc Power Take Offs ............. 66



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Table of Contents



Twin Disc, Incorporated



Operation ..............................................................69 General Information ............................................................................ 69 Clutch Engagement Procedure .......................................................... 70



Maintenance .........................................................73 Maintenance Tips ................................................................................ 73 Lubrication .......................................................................................... 76 Clutch Adjustment .............................................................................. 79 Friction Plate Replacement ................................................................ 80 Field Adjustment - Tapered Roller Bearings (side-loaded pto applications) (Except SB Models) ............................................................. 81 Checking Bearing End Play - Model SP318SB Series Only ............. 82 Bearing End Play - Tapered Roller Bearings used with In-Line Applications ............................................................................................. 84



Disassembly .........................................................85 Power Take-off Removal From The Engine ....................................... 86 Clutch Removal ................................................................................... 87 Clutch Disassembly ............................................................................ 88 Bronze Collar Disassembly ................................................................ 88 Ball Bearing Collar Disassembly ....................................................... 88 Remove the Operating Shaft and Throwout Yoke............................. 90 Clutch Shaft and Housing Disassembly - Configuration A .............. 91 Clutch Shaft and Housing Disassembly - Configuration B .............. 93 Clutch Shaft and Housing Disassembly - Configuration C .............. 95 Clutch Shaft and Housing Disassembly - Configuration D .............. 97



Cleaning and Inspection ......................................99 Cleaning and Inspection ..................................................................... 99



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Power Take-Off Service Manual #1022764



Twin Disc, Incorporated



Table of Contents



Assembly.............................................................103 Clutch Assembly ............................................................................... 104 Clutch Shaft and Housing Assembly - Configuration A .................. 111 Clutch Shaft and Housing Assembly - Configuration B ................. 121 Clutch Shaft and Housing Assembly - Configuration C ................. 124 Clutch Shaft and Housing Assembly - Configuration D ................. 127 Install the Operating Shaft and Throwout Yoke. ............................. 133 PTO Final Assembly .......................................................................... 135



Illustrations .........................................................139 List of Illustrations ............................................................................ 139 Parts Identification List - SP218, SP318, SP318SB, and SP321 Series ... 140 Exploded View (SP218 and SP318 Series Clutches) ..................... 141 Exploded View (SP321 Series Clutch) ............................................ 142 Exploded View (Configuration A) ..................................................... 143 Exploded View (Configuration B)..................................................... 144 Exploded View (Configuration C)..................................................... 145 Exploded View (Configuration D)..................................................... 146



Engineering Drawings .......................................147 SP218P001 Sheet 2 of 2 (Typical Configuration A) ......................... 148 SP318P001 Sheet 2 of 2 (Typical Configuration B) ......................... 149 SP318P011 Sheet 2 of 2 (Typical Configuration C) ......................... 150 SP318S001 Sheet 2 of 2 (Typical Configuration D) ......................... 151 SP321P901 Sheet 2 of 2 (Typical Configuration B) ......................... 152 SP218 Clutch SP218C001 Sheet 2 of 2 ............................................ 153 SP318 Clutch SP318C001 Sheet 2 of 2 ............................................ 154 SP318 Clutch SP318C003 Sheet 2 of 2 ............................................ 155 SP321 Clutch SP321C001 Sheet 2 of 2 ............................................ 156



Power Take-Off Service Manual #1022764



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Table of Contents



Twin Disc, Incorporated



NOTES



10



Power Take-Off Service Manual #1022764



Twin Disc, Incorporated



Introduction



Introduction



General Information This publication provides the information necessary for the operation and maintenance of the Twin Disc, Incorporated equipment specified on the cover of this manual. Specific engineering details and performance characteristics can be obtained from the Product Service Department of Twin Disc, Incorporated, Racine, Wisconsin, USA. Operation and maintenance personnel responsible for this equipment should have this manual at their disposal and be familiar with its contents. Applying the information in the manual will result in consistent performance from the unit and help reduce downtime.



Power Take-off Service Manual #1022764



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Introduction



Twin Disc, Incorporated



Replacement Parts



Parts Lists See the engineering assembly drawings in Engineering Drawings, parts identification and exploded views in the Illustrations section to facilitate ordering spare or replacement parts.



Ordering Parts



All replacement parts or products (including hoses and fittings) must be of Twin Disc origin or equal, and otherwise identical with components of the original equipment. Use of any other parts or products will void the warranty and may result in malfunction or accident, causing injury to personnel and /or serious damage to the equipment. Renewal parts and service parts kits may be obtained from any authorized Twin Disc distributor or service dealer.



Parts Shipment Furnish the complete shipping information and postal address. All parts shipments made from the factory will be FOB factory location, USA. State specifically whether the parts are to be shipped by freight, express, etc. If shipping instructions are not specified, the equipment will be shipped the best way, considering time and expense. Twin Disc, Incorporated will not be responsible for any charges incurred by this procedure. Twin Disc, Incorporated having stipulated the bill of material number on the unit’s nameplate absolves itself of any responsibility resulting from any external, internal or installation changes made in the field without the express written approval of Twin Disc. All returned parts, new or old, emanating from any of the above-stated changes will not be accepted for credit. Furthermore, any equipment which has been subjected to such changes will not be covered by a Twin Disc warranty.



12



Power Take-off Service Manual #1022764



Twin Disc, Incorporated



Introduction



Preventive Maintenance/Troubleshooting



Frequent reference to the information provided in this manual regarding daily operation and limitations of this equipment will assist in obtaining troublefree operation. Schedules are provided for the recommended maintenance of the equipment and, if observed, minimum repairs (aside from normal wear) will result. In the event a malfunction does occur, a troubleshooting table is provided to help identify the problem area and lists information that will help determine the extent of the repairs necessary to get a unit back into operation.



Lifting Bolt Holes Most Twin Disc products have provisions for attaching lifting bolts. The holes provided are always of adequate size and number to safely lift the Twin Disc product.



These lifting points must not be used to lift the complete power unit. Lifting excessive loads at these points could cause failure at the lift point (or points) and result in damage or personal injury.



Select lifting eyebolts to obtain maximum thread engagement with bolt shoulder tight against housing. Bolts should be near but should not contact bottom of bolt hole.



Power Take-off Service Manual #1022764



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Introduction



Twin Disc, Incorporated



Safety



General Safe practices must be employed by all personnel operating and servicing this unit. Twin Disc, Incorporated will not be responsible for personal injury resulting from careless use of hand tools, lifting equipment, power tools, or unaccepted maintenance/operating practices.



Important Safety Notice Because of the possible danger to person(s) or property from accidents which may result from the use of manufactured products, it is important that correct procedures be followed. Products must be used in accordance with the engineering information specified. Proper installation, maintenance, and operation procedures must be observed. Inspection should be made as necessary to assure safe operations under prevailing conditions. Proper guards and other suitable safety codes should be provided. These devices are neither provided by Twin Disc, Incorporated nor are they the responsibility of Twin Disc, Incorporated.



14



Power Take-off Service Manual #1022764



Twin Disc, Incorporated



Introduction



Sources of Service Information



Each series of manuals issued by Twin Disc, Incorporated is current at the time of printing. When required, changes are made to reflect advancing technology and improvements in state-of-the-art. Individual product service bulletins are issued to provide the field with immediate notice of new service information. For the latest service information on Twin Disc products, contact any Twin Disc distributor, or contact the Product Service Department, Twin Disc, Incorporated, Racine, Wisconsin 53405-3698, USA by e-mail at [email protected]. Contact information for Authorized Twin Disc Distributors and Service Dealers can be found on the Twin Disc Web site at: http://www.twindisc.com.



Power Take-off Service Manual #1022764



15



Introduction



Twin Disc, Incorporated



Warranty



Equipment for which this manual was written has a limited warranty. For details of the warranty, refer to the warranty statement at the front of this manual.



16



Power Take-off Service Manual #1022764



Twin Disc, Incorporated



Description and Specifications



Description and Specifications



General Information The SP218, SP318, SP318SB and SP321 Series Twin Disc Power Take-Offs are engine-mounted power take offs that use cast iron one-piece or two-piece housings and contain an integral clutch 18 or 21 inches in diameter. The engine drives the clutch through a drive ring that is bolted to the engine flywheel and connected to the clutch through internal teeth that mesh with external teeth on the clutch friction plates. Clutch engagement and disengagement for most units is accomplished by use of the external hand lever assembly. Some units may use other actuation methods. Main bearings are lubricated and cooled with oil or grease, depending upon the design specifications. Most units use pilot bearings that are pre-lubricated and sealed for life, although some may require periodic relubrication. Those that require periodic relubrication are lubricated through a grease fitting located in the output end or side of the clutch shaft.



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Description and Specifications



Twin Disc, Incorporated



Identifying the Twin Disc Power Take-Off Model Number



The nameplate identifies the model, bill of material (BOM) and the serial number of the unit. These numbers are necessary to identify the correct parts for your Power Take-Off.



BOM No.



Model No.



S/N Information and instructions specific to each individual PTO. Figure 1. Representative Instruction Plate



18



Power Take-off Service Manual #1022764



Twin Disc, Incorporated



Description and Specifications



Identifying the Twin Disc Power Take-off Model



Typical Model Identification Number: SP318P-0 3



18



P -



0



A



B



C



D



E



{ { { { {



SP



A.



Indicates the type of clutch. SP = Counter balanced, toggle action overcenter clutch



B.



Indicates the number of friction plates in the clutch. 2 = 2 clutch driving plates 3 = 3 clutch driving plates



C.



Indicates the nominal size of the clutch driving plates (inches). 18 = 18” diameter (nominal), measured just inside the root of the teeth 21 = 21” diameter (nominal), measured just inside the root of the teeth



D.



Indicates the housing design. P = standard (grease lubricated) main bearings OP = oil lubricated main bearings IL = main bearings for in-line duty only SB = straddle bearing design



E.



Indicates the S.A.E. housing size. 0 = SAE # 0 housing 00 = SAE # 00 housing



Power Take-off Service Manual #1022764



19



Description and Specifications



Twin Disc, Incorporated



Twin Disc Power Take-Off Reference Listing



The Twin Disc Power Take-Off Reference Listing on the following pages refers to various basic design configuration designations used for the main bearing housing. These designations are used primarily to simplify explanation of the disassembly and assembly procedures in this manual. The following chart provides a general description of the basic features of each configuration and also provides general information regarding each Twin Disc Power Take-Off. However, always refer to a current BOM for your specific power take-off to insure that the most up-to-date information is being used. Configuration Feature



A



B



C



X



X



X



D



Main Housing and Bearing Carrier 2-piece (Separate Items) 2-Piece straddle bearing design Assembly of Main Bearings From opposite ends of shaft (Both) from one end of shaft Retention of Main Bearing(s) Retained by bearing retainer(s) Retained by snap ring(s) Bearing Retainer Bolted Both front and rear retainers used Retention of Bearing Retainer Retained by bolts Main Bearing Adjustment Shims No adjustment Oil Seals in Housing or Brg. Carrier Wear Sleeve(s) on Shaft



20



X X



X X



X



X



X X



X



X



X



X



X



X X



X



X



X



X



X



X



X



X X X



Power Take-off Service Manual #1022764



Twin Disc, Incorporated



Description and Specifications



SP218P001 SP218P002 SP218P003 SP218P004 SP218P005 SP218P008 SP218P009 SP318P001 SP318P002 SP318P003 SP318P004 SP318P005 SP318P009 SP318P010 SP318P011 SP318P012 SP318P013 SP318P014 SP318S001 SP318S002 SP318S004 SP318S005 SP318S006 SP318S007 SP321P901 SP321P902 SP321P903 SP321P904 SP321P905



X X X X X X X X X X X X X X X X X X X X X X X X X X X X X



X X X X



X X X X X X X X



Power Take-off Service Manual #1022764



X X X X not used not used X X not used not used not used not used not used not used X X



X



X X X X X X X X X X X X X X X X X X X X X X X X X X X X X



X X X X X X X X X X X X X X X X X X X X X X X X X X X X X



X X X X X X X X X X X X X X X X X X X X X X X X X X X X X



Facing Type



Split



Nodular



Cast Iron



Roller



X X X X



X X



X X X X X



Ball



Ball



Bronze



X X X X X X X X X X X X X X



Drive Ring Type



Support Plate Req’d



SP218OP0 SP218OP0 SP218OP0 SP218OP0 SP218OP0 SP218OP0 SP218OP00 SP318P0 SP318P0 SP318P0 SP318P0 SP318P0 SP318P0 SP318P0 SP318IL0 SP318IL0 SP318P0 SP318P0 SP318SB0 SP318SB0 SP318SB0 SP318SB0 SP318SB0 SP318SB0 SP321P00 SP321P00 SP321P00 SP321P00 SP321P00



Oil



Grease



Main Bearing Throwout Pilot Bearing Lubrication Collar Type Type



Solid



Twin Disc Power Take-Off Reference Listing



Main Bearing Housing Configuration



A A A A A A A B B B B B B B C C B B D D D D D D B B B B B



21



Description and Specifications



Twin Disc, Incorporated



Identifying the SAE Housing Size



D A



B



C



Table 1. SAE Housing Identification A



Housing SAE Housing Pilot Diameter Size mm.



22



inches



B



C



D



Housing Flange O.D.



Bolt Circle Diameter



Bolt Holes Dia.



Qty. mm.



inches



mm.



inches



mm.



inches



0



647.70 25.500



711.2



28.00



679.45 26.750 16



14.30



0.563



00



784.40 31.00



882.6



34.75



850.90 33.50



14.30



0.563



16



Power Take-off Service Manual #1022764



Twin Disc, Incorporated



Description and Specifications



Specifications Maximum Safe Operating Speeds for Twin Disc Power Take-offs (Refer to BOM and Twin Disc Reference Listing on previous pages.) Table 2. Maximum Safe Operating Speeds Cast Iron Drive Ring Grease- or OilSolid lubricated Main Drive Plate(s) Bearing(s)



PTO Model



Split Drive Plate



Steel or Nodular Drive Ring Solid Drive Plate(s)



Split Drive Plate



SP218 Series



Oil



1950



1550



2350



2100



SP318 Series



Grease



2050



1550



2350



2100



SP318SB Series



Grease



n/a



n/a



2350



n/a



SP321 Series



Grease



1800



1400



1800



1800



Pilot bearing position (If used) (Refer to BOM and Twin Disc Reference Listing on previous pages.)



Ball-Type The owner/operator is responsible for checking the flywheel to ensure that the pilot bearing is installed on the shaft with sufficient clearance without bottoming in the flywheel bore. The depth of the pilot bore from the flywheel housing face to shoulder on the flywheel pilot flange is 100.07 mm. (3.94 in.).



Roller-Type Table 3. Roller-Type Pilot Bearing Dimensions Roller



Bearing O.D.



Bearing



Bearing Nominal



Bearing Nominal



Width (C)



Width +/- tolerance



M2713 100 mm. (3.94 in.) 39.62 mm. (1.5600 in.) 0.5 mm. (0.0025 in.)



Power Take-off Service Manual #1022764



23



Description and Specifications



Twin Disc, Incorporated



Tapered Roller Bearing End Play Table 4. Recommended Bearing End Play for Tapered Roller Bearings Used in Side-Loaded applications Recommended End Play Model Number



mm.



inches



SP218OP Series



0.15 - 0.25



0.006 - 0.010



SP318P Series



n/a (Ball Bearing) n/a (Ball Bearing)



SP318IL Series



n/a (Ball Bearing) n/a (Ball Bearing)



SP318SB Series



n/a (Ball Bearing) n/a (Ball Bearing)



SP321P Series



n/a (Ball Bearing) n/a (Ball Bearing)



Table 5. Recommended Bearing End Play for Tapered Roller Bearings Used in In-Line applications Recommended End Play Model Number



mm.



inches



SP218OP Series



0.23 - 0.30



0.009 - 0.012



SP318P Series



n/a (Ball Bearing) n/a (Ball Bearing)



SP318IL Series



n/a (Ball Bearing) n/a (Ball Bearing)



SP318SB Series



n/a (Ball Bearing) n/a (Ball Bearing)



SP321P Series



n/a (Ball Bearing) n/a (Ball Bearing)



Hub Nut Advance Table 6. Hub Nut Advance After Initial Tightening Model Number



24



Rotate Hub Nut Clockwise the Additional Amount Shown



SP218OP Series



180 - 210 degrees



SP318P Series



240 - 270 degrees



SP318IL Series



150 - 180 degrees



SP318SB Series



150 - 180 degrees



SP321P Series



210 - 240 degrees Power Take-off Service Manual #1022764



Twin Disc, Incorporated



Description and Specifications



Filling the Main Bearing Cavity during initial assembly. (Refer to BOM, Twin Disc Reference Listing on previous pages and Exploded Views in the Illustration Section.) Grease Lubrication: Hand-pack the bearings before assembly. Hand-packing requires that the roller elements and bearing races be coated with grease. After assembly, add grease through the grease fitting until grease escapes from the outboard labyrinth seal all around the shaft. Do Not Overfill. Always rotate the shaft while adding grease to the bearing cavity. Grease Lubrication with Purge Plug in Bottom of Bearing Carrier: Some models (configuration B, for example) were designed with a plug (71) at the bottom of the bearing carrier to help purge the old grease from the cavity when new grease is added. Hand-pack the bearings before assembly. Hand-packing requires that the roller elements and bearing races be coated with grease. After assembly, remove the purge plug before grease is added. Add grease through the grease fitting (51) until grease is visible in the open hole. Always rotate the shaft while adding grease to the bearing cavity. Run the PTO 1/2 hour until excess grease drains out. Then reinstall the plug. Note: Bearings will run hot if overfilled. Oil Lubrication SP214OP Series: Fill with oil through the fill fitting (72) at the top of the bearing carrier until the oil level reaches the proper level shown on the oil gauge (66).



Filling the Main Bearing Cavity during periodic maintenance. Refer to the information contained in the Maintenance section of this manual.



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Description and Specifications



Twin Disc, Incorporated



Engagement force on the operating shaft Table 7. Torque at Operating Shaft to Engage Clutch Model



Peak Torque on Operating Shaft Nm Lb.-Ft.



SP218 Series



691 - 916



510 - 676



SP318 Series



691 - 916



510 - 676



SP318SB Series



691 - 916



510 - 676



SP321 Series



691 - 916



510 - 676



PTO Deflection PTO deflection due to loads imposed by the application should not exceed 0.254 mm (0.010 in.). Deflection should be measured at the support plate pilot with the dial indicator base mounted on a rigid part of the engine. See the illustration in Installation Tips in the Installation section of this manual.



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Power Take-off Service Manual #1022764



Twin Disc, Incorporated



Description and Specifications



Twin Disc PTO Support Plate Specifications Twin Disc, Inc. requires that a support plate be used with SP218, SP318, SP318SB and SP321 Series models used in side-load applications and recommends that a support plate be used for in-line applications. (angle to first hole)



D



C (radius)



(Holes)



E (Qty.) F (dia.)



B (diameter)



A (diameter)



G



Shim to within .12 cm. (.005 in.) 43.18 cm. (17.0 in.)



Figure 2. Typical Support Plate Illustration



Table 8. Support Plate Dimensions PTO Model



A Bore Dia. +.127/.025mm (+.005/+.001”)



B Bolt Circle (Dia.)



C Radius



D Degree



E F Hole Hole Quantity Diameter



G Recommended Thickness



SP218OP



317.50 mm. 355.60 mm. 196.85 mm. (12.500 in.) (14.000 in.) (7.75 in.)



45°



8



11/16 in.



19.05 mm. (0.750 in.)



SP318P



254.00 mm. 304.80 mm. 177.80 mm. (10.000 in.) (12.000 in.) (7.00 in.)



30°



6



11/16 in.



19.05 mm. (0.750 in.)



SP318SB



238.15 mm. 285.75 mm. 168.15 mm. (9.376 in.) (11.25 in.) (6.62 in.)



**



6



17/32 in.



19.05 mm. (0.750 in.)



SP3121P



279.40 mm. 330.20 mm. 190.50 mm. (11.000 in.) (13.000 in.) (7.50 in.)



30°



6



11/16 in.



19.05 mm. (0.750 in.)



** Refer to assembly drawing. Angular offset of the through holes must be calculated with respect to orientation of sheave housing. Holes are equally spaced.



Note: One possible mounting method provides installation ease. Use angle iron to couple the support plate to the engine frame. Power Take-off Service Manual #1022764



27



Description and Specifications



Twin Disc, Incorporated



Wear Limits



Table 9. Wear Limits - Bearing Carrier Bore Dimensions (Refer to BOM for the Bearing Carrier/Housing Part Number used in your PTO.)



Housing, Sheave Housing or Bearing Carrier Part Number



28



Bore Dim. A (Maximum)



Bore Dim. B (Maximum)



Illustration Number



mm.



inches



mm.



inches



9679



200.0453



7.8758



n/a



n/a



2



9693



230.0453



9.0569



n/a



n/a



2



1016454



180.0350



7.0880 180.0350 7.0880



3



A6867E



157.2133



6.1895



n/a



n/a



1



A7574



215.0466



8.4664



n/a



n/a



4



A7576



170.0378



6.6944



n/a



n/a



5



A7576A



170.0378



6.6944



n/a



n/a



5



Power Take-off Service Manual #1022764



Twin Disc, Incorporated



Description and Specifications



A 1



A 2 A



A



3 B



4



5 A



Figure 3. Housing/Bearing Carrier Illustrations



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Description and Specifications



Twin Disc, Incorporated



Table 10. Wear Limits - Shaft Dimensions (Refer to BOM for the Clutch Shaft Part Number used in your PTO)



Shaft Part Number



Main Bearing Journal Dim. A (Min.)



mm.



mm.



inches



inches



Main Bearing Journal Dim. B (Min.)



mm.



inches



Illus. Number



A6678H



44.9986 1.7716 120.0125 4.7249



n/a



n/a



2



A6678K



54.9962 2.1653 120.0125 4.7249



n/a



n/a



2



A6697



51.9973 2.3621 130.0277 5.1192



n/a



n/a



2



A6697J



51.9973 2.3621 130.0277 5.1192



n/a



n/a



2



A6697K



51.9973 2.3621 130.0277 5.1192



n/a



n/a



2



A7577A



none



none 120.0125 4.7249



80.0125 3.1501



4



A7598



none



none 120.0125 4.7249



80.0125 3.1501



4



B5908



44.9986 1.7716 101.6381 4.0015 101.6381 4.0015



1



B5908B



34.9987 1.3779 101.6381 4.0015 101.6381 4.0015



1



B5909



54.9962 2.1653 101.6381 4.0015 101.6381 4.0015



1



1016689



30



Pilot Bearing Journal (Min.)



none



none 120.0150 4.7250 120.0150 4.7250



3



Power Take-off Service Manual #1022764



Twin Disc, Incorporated



Description and Specifications



Pilot Bearing Journal



Main Bearing Journal A (and seal journal)



1 Main Bearing Journal B (and seal journal)



Pilot Bearing Journal



Main Bearing Journal A



2



Main Bearing Journal A



3



Main Bearing Journal B Main Bearing Journal A



4 Main Bearing Journal B



Figure 4. Clutch Shaft Illustrations Power Take-off Service Manual #1022764



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Description and Specifications



Twin Disc, Incorporated



Torque Values for Fasteners Note: The tables below provide information for several different types of fasteners: U.S. Standard Fine and Coarse Thread Capscrews, Bolts, and Nuts; Metric Coarse Thread Capscrews, Bolts, and Nuts; Tapered Pipe Plugs (with thread lubricant); Straight Threaded Tube Fittings, Hose Fittings, and O-ring Plugs. Be sure to use the appropriate table to obtain the correct torque value. Note: All threads and bearing face to be lubricated with light oil film prior to assembly.



Table 11. U.S. Standard Fine and Coarse Thread Capscrews, Bolts, and Nuts



SAE Grade 5



Thread Diameter N-m



32



SAE Grade 8



lb.-ft.



N-m



lb.-ft.



1/4



8 - 11



6-8



14 - 16



10 - 12



5/16



18 - 23



13 - 17



27 - 33



20 - 24



3/8



34 - 39



25 - 29



47 - 56



35 - 41



7/16



50 - 58



37 - 43



75 - 88



55 - 65



1/2



81 - 95



60 - 70



113 - 132



83 - 97



9/16



111 - 133



82 - 98



163 - 190



120 - 140



5/8



163 - 190



120 - 140



224 - 264



165 - 195



3/4



278 - 332



205 - 245



400 - 468



295 - 345



7/8



447 - 529



330 - 390



637 - 746



470 - 550



1



671 - 793



495 - 585



969 - 1132



715 - 835



1 1/8



834 - 997



615 - 735



1376 - 1607



1015 - 1185



1 1/4



1152 - 1356



850 - 1000



1864 - 2203



1375 - 1625



Power Take-off Service Manual #1022764



Twin Disc, Incorporated



Description and Specifications



Table 12. Metric Coarse Thread Capscrews, Bolts, and Nuts



Property Class 8.8



Thread Size



Property Class 10.9



Property Class 12.9



N-m



lb.-ft.



N-m



lb.-ft.



N-m



lb.-ft.



M6



9 -10



6.5 - 7.5



12 - 14



9 - 10



14 - 16



10 - 12



M8



21 -25



16 - 18



31 - 35



23 - 26



34 - 40



25 - 29



M10



43 - 49



32 - 36



60 - 68



44 - 51



70 - 80



51 - 59



M12



74 - 86



55 - 63



104 - 120



77 - 88



121 - 139



89 - 103



M16



179 - 205



132 - 151



256 - 294



189 - 217



298 - 342



219 - 253



M18



247 - 281



182 - 208



350 - 398



258 - 294



412 - 469



304 - 346



M20



348 - 400



257 - 295



493 - 567



364 - 418



581 - 669



429 - 493



M22



475 - 541



351 - 399



669 - 762



494 - 562



792 - 902



584 - 666



M24



603 - 693



445 - 511



848 - 976



626 - 720



1000 - 1150



737 - 848



M30



967 - 1113 714 - 820



1674 - 1926



1235 - 1421



2000 - 2301 1475 - 1697



Table 13. Tapered Pipe Plugs (with thread lubricant)



NPTF Size (in.)



In Cast Iron or Steel



In Aluminum



N-m (+ or - 5%) lb.-ft. (+ or - 5%) N-m (+ or - 5%) lb.-ft. (+ or - 5%)



1/6-27



11.5



8.5



7.5



5.5



1/8-27



14



10.5



9



6.5



1/4-18



34



25



21.5



16



3/8-18



36.5



27



23



17



1/2-14



68



50



40.5



30



3/4-14



73



54



46



34



1-11 1/2



108



80



68



50



1 1/4-11 1/2



115



85



75



55



1 1/2-11 1/2



115



85



75



55



Power Take-off Service Manual #1022764



33



Description and Specifications



Twin Disc, Incorporated



Table 14. Straight Threaded Tube Fittings, Hose Fittings, and O-ring Plugs Nominal Nominal Thread N-m (+ or - 5%) lb.-ft. (+ or - 5%) Thread N-m (+ or - 5%) lb.-ft. (+ or - 5%) Diameter Diameter



34



5/16



5



3.5



M10X1.0



12



9



3/8



11.5



8.5



M12X1.5



16



12



7/16



16



12



M14X1.5



20



15



1/2



20



15



M16X1.5



24



18



9/16



24.5



18



M18X1.5



34



25



5/8



24.5



18



M22X1.5



54



40



11/16



34



25



M27X2.0



75



55



3/4



40.5



30



(in iron)



7/8



54



40



M27X2.0



75



55



1 1/16



75



55



(in aluminum)



1 3/16



88



65



M33X2.0



88



65



1 1/4



88



65



M42X2.0



108



80



1 5/16



108



80



M48X2.0



108



80



1 3/8



108



80



1 5/8



108



80



1 7/8



108



80



2 1/2



108



80



Power Take-off Service Manual #1022764



Installation



Twin Disc, Incorporated



Installation



Installation Tips



Tapered Roller Bearing Adjustment 1.



Tapered roller bearing end play adjustment is different in SP218 Series Power Take-Offs for side load applications than it is for in-line applications. Insure that the adjustment is correct for the application.



2.



All SP218 Series Power Take-Offs are manufactured at Twin Disc’s factory with the tapered roller bearing end play adjusted for side-load application.



3.



SP318 and SP321Series Power Take-Offs have ball- or spherical rollertype main bearings. No adjustment is required.



4.



Tapered roller bearing end play in SP218 Series Power Take-Offs used for in-line applications must be adjusted to specifications shown in Tapered Roller Bearing End Play in the Description and Specifications section of this manual. a.



For rebuilt or remanufactured PTOs: Adjust the end play to proper specifications for in-line applications at the time of assembly. Follow instructions contained in the Assembly section of this manual.



Power Take-Off Service Manual #1022764



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Installation



Twin Disc, Incorporated



b.



For SP218 Series PTOs manufactured in Twin Disc’s factory: Readjust the factory end play setting prior to installation on the engine for in-line applications. Most SP218 Series Power Take-Offs have a tag attached to the housing which contains instructions that must be followed. Readjust the end play setting as instructed.



Figure 5. Factory Instruction Tag for End Play Adjustment



Alignment 5.



The flywheel and flywheel housing alignment must be within specifications. Perform the measurements shown in Prior To Installation in this Installation section.



6.



Avoid excessive misalignment between the engine and PTO. Check the following if abnormal wear of parts exists: a.



Excessive loads tend to deflect parts to which PTOs are mounted. A dial indicator can be mounted on a rigid part of the engine or independently on the foundation to determine deflection under actual operating conditions. See Support Plate, Belt or chain tension/Allowable Side Load Pulls and Deflection Caused by Side Load Pulls in this Installation section and information contained in the Description and Specifications section regarding these issues



b.



Readings taken before the drive is installed with the engine standing still and when under operating conditions (with the engine off and all belts, chains, driveshafts and/or support plates attached and secured with bolts torqued to specifications) will indicate the extent of deflection. In no case should the deflection exceed 0.254 mm. (0.010 in.) (T.I.R.) at the bearing carrier.



Note: The dial indicator should never be applied with the engine running. This is unsafe and could result in damage to the dial indicator. 36



Power Take-Off Service Manual #1022764



Installation



Twin Disc, Incorporated



7.



In a u-joint-type installation, to realize the longest possible life of the power take-off bearings, the best possible alignment must be maintained between the center line of the power take-off shaft and the center line of the driven unit shaft. See information contained in Alignment-U-JointType Installation in this Installation section.



8.



In side-load installations, alignment between the driveR and driveN pulleys must be carefully established and maintained. See Position and Measure Alignment of the Sheave in this Installation section.



Drive Ring 9.



The drive ring must be properly installed. See information in Drive Ring Installation in this Installation section.



Pilot Bearings 10.



Ball-type pilot bearings and Roller-type pilot bearings must be installed properly. See Ball-Type Pilot Bearing Installation or Roller-Type Pilot Bearing Installation in this Installation section.



Support Plate 11.



When mounting the engine and Power Take Off in the machine, a customer-supplied support plate may be required to support the output end of the pto housing. See the information about customer-supplied support plates and Twin Disc Support Plate Specifications contained in the Description and Specifications section of this manual.



Failure to follow this requirement may result in damage to the power take off or the engine flywheel housing.



Belt or chain tension/Allowable Side Load Pulls 12.



Avoid excessive tightening of belts or chains. See the Allowable Side Load tables in this Installation section.



13.



Avoid excessively loose belts or chains. Belt tension or chain adjustment that is below specifications can cause belt/chain “whip” during operation, resulting in bearing failure and shortened power take-off service life.



Power Take-Off Service Manual #1022764



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Twin Disc, Incorporated



Deflection Caused by Side Load Pulls 14.



Power Take-Off deflection due to loads imposed by the application should not exceed specified limits shown in PTO Deflection in the Description and Specifications section. Deflection should be measured at the support plate location on the power take-off (or main bearing area of the housing if no support plate is used).



Figure 6. Determining Deflection While Applying Side Loads



The dial indicator should not be applied while the unit is operating. This could result in damage to the dial indicator.



Lubrication 15.



38



Verify that the PTO is properly lubricated prior to starting the engine. a.



The throwout collar is lubricated by grease through a grease fitting on the outside of the main housing.



b.



SP218OP Series main bearings are lubricated by oil contained in the main bearing cavity.



Power Take-Off Service Manual #1022764



Installation



Twin Disc, Incorporated



c.



All SP318 and SP321 Series main bearings are lubricated by grease through a grease fitting in the housing or bearing carrier.



d.



The sealed-for-life pilot bearing should not be lubricated during service.



e.



Pilot bearings designed for periodic lubrication must be greased. See Lubrication in the Maintenance section for more information. Improper lubrication will result in premature failure of components. DO NOT OVERGREASE!



Refer to the Twin Disc Power Take-Off Reference Listing and Filling the Main Bearing Cavity in the Description and Specifications section, Lubrication in the Maintenance section and Engineering Drawings near the back of this manual.



Clutch Adjustment 16.



Verify that the clutch is adjusted according to the procedure outlined in Clutch Adjustment in the Maintenance section. Failure to do so will result in premature clutch wear and failure. Note: Twin Disc will not be responsible for any damage or injury resulting from improper adjustment and/or lubrication. This includes any accessory drives and loads.



Hand Lever Position 17.



Proper hand lever position is required to obtain long service life of the throwout bearing. See Hand Lever Position for Twin Disc Power Take-Offs in this Installation section.



Air Engagement Mechanisms 18.



Air engagement mechanisms must be installed and adjusted properly for proper clutch actuation and long service life of the PTO. No preload on the throwout bearing can exist either in the fully-engaged or fullyreleased positions, and the air mechanism must be engineered and installed to provide proper engagement force and stroke to properly engage and disengage the clutch. See Setting Up Air Engagement on Twin Disc Power Take-Offs in this Installation section.



Power Take-Off Service Manual #1022764



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Installation



Twin Disc, Incorporated



Prior to Installation (Ref: SAE J1033 and J617) Refer to Identifying the SAE Housing Size in the Description and Specifications section of this manual.



Most Twin Disc products mount directly onto the flywheel of the engine. Flywheel-to-driven component interference is possible due to mismatch of components or other reasons. Therefore, engine crankshaft endplay as well as flywheel alignment check must be made before the driven component, the Power Take-Off, is installed. After installation of the Power Take-Off, crankshaft end play should be measured again. End play at the second measurement should be the same as the first. A difference in these two end play measurements could be an indication of interference. Consequently, the Power Take-Off should be removed and the source of interference found and corrected. Twin Disc will not be responsible for system damage caused by engine to Twin Disc match-up regardless of the cause of interference. This engine crankshaft end play check is considered mandatory. Note: All measurements must be taken with the engine or motor mounted on its supports after the flywheel and housing have been thoroughly cleaned. 1.



40



Measure and record the engine crankshaft or motor shaft endplay using a dial indicator. Record this value, as it will be used later._______



Power Take-Off Service Manual #1022764



Installation



Twin Disc, Incorporated



2.



Bolt the indicator to the flywheel so the indicator is perpendicular to the flywheel housing face and the indicator stem rides on the flywheel housing face.



Figure 7. Checking Flywheel Housing Face 3.



Rotate the shaft through on entire revolution and note the runout. The total indicator reading (T.I.R.) must not exceed: SAE #0 Housing 0.41 mm. (0.016 in.) SAE #00 Housing 0.48 mm. (0.019 in.) Note: The flywheel and crankshaft of the engine must be held against either the front or rear of the crankshaft thrust bearing while the total indicator sweep (T.I.R.) is being made.



Power Take-Off Service Manual #1022764



41



Installation



Twin Disc, Incorporated



4.



Readjust the indicator so the stem rides on the pilot bore of the flywheel housing face.



Figure 8. Checking Flywheel Housing Bore 5.



Rotate the shaft through one entire revolution and note the runout. The total indicator reading (T.I.R.) should not exceed: SAE #0 Housing 0.41 mm. (0.016 in.) SAE #00 Housing 0.48 mm. (0.019 in.)



6.



Remove the indicator base from the flywheel and bolt it to the flywheel housing face. Position the indicator stem so that it rides where the drive ring will set on the flywheel face.



Figure 9. Checking Driving Ring Surface of Flywheel 7.



Rotate the shaft through one entire revolution and note the face runout of the flywheel. The total indicator reading (T.I.R.) must not exceed 0.01mm. (0.0005 in.) per 25.4 mm. (per inch) of flywheel diameter. Note: The flywheel and crankshaft of the engine must be held against either the front or rear of the crankshaft thrust bearing while the total indicator sweep (T.I.R.) is being made.



42



Power Take-Off Service Manual #1022764



Installation



Twin Disc, Incorporated



8.



Readjust the indicator stem so it rides on the driving ring pilot bore of the flywheel.



Figure 10. Checking Driving Ring Pilot Bore of Flywheel 9.



Rotate the shaft through one entire revolution and note the driving ring bore eccentricity. The total indicator reading (T.I.R.) must not exceed 0.13 mm. (0.005 in.).



10.



Adjust the indicator stem so that it rides on the pilot bearing bore cavity.



Figure 11. Checking Pilot Bearing Bore of Flywheel 11.



Rotate the shaft through one entire revolution and note the pilot bearing bore eccentricity. The total indicator reading (T.I.R.) must not exceed 0.13 mm. (0.005 in.). Note: Eccentricity between the driving ring pilot bore and the pilot bearing bore must not exceed 0.20 mm. (0.008 in.).



Power Take-Off Service Manual #1022764



43



Installation



Twin Disc, Incorporated



Drive Ring Installation Refer to information regarding cleaning and inspection in the Cleaning and Inspection section of this manual before proceeding. 1.



Clean the drive ring and flywheel of any dirt or debris as necessary.



2.



Use crocus cloth or emery cloth to remove any surface imperfections such as nicks, burrs, and sharp edges on the O.D. or the surface that will be mounted against the flywheel face.



3.



Use crocus cloth or emery cloth to remove any surface imperfections such as nicks, burrs, and sharp edges in the I.D. of the flywheel pilot bore or on the face that will be in contact with the drive ring.



4.



Position the drive ring against the flywheel, piloted in the mounting bore, and secure with hex-head capscrews (six for 18” clutches or twelve for 21” clutches). Torque the capscrew to the proper specifications given in Torque Values for Fasteners in the Description and Specifications section of this manual.



Drive ring attachment screws must be grade 8. Do not use substitutes.



44



Power Take-Off Service Manual #1022764



Installation



Twin Disc, Incorporated



Ball-Type Pilot Bearing Installation Refer to the Twin Disc Power Take-Off Reference Listing in the Description and Specifications section, the exploded views in the Illustration section and Engineering Drawings near the back of this manual. Refer to information regarding cleaning and inspection in the Cleaning and Inspection section of this manual before proceeding. 1.



Support the output end of the clutch shaft.



2.



Make sure the clutch shaft end stub is free of surface imperfections such as nicks, burrs, and sharp edges. Remove them using fine emery cloth or crocus cloth.



3.



Tap the pilot bearing onto the clutch shaft. The front face of the pilot bearing should be positioned flush with the input end of the clutch shaft. Tap or apply force to only the inner race of the bearing. Note: Tap or press only on the inner race of the bearing. Any impact on the outer race or balls will damage the bearing, resulting in shortened service life or premature failure.



Do not damage the seal of the pilot bearing. A damaged seal renders the pilot bearing destroyed and it must be replace with a new bearing.



Front of Pilot Bearing Flush with End of Clutch Shaft



Clutch Shaft Pilot Bearing (Ball-type shown) Figure 12. Position of the Ball-Type Pilot Bearing on the Shaft



Power Take-Off Service Manual #1022764



45



Installation



Twin Disc, Incorporated



Roller-Type Pilot Bearing Installation Some Twin Disc Power Take-offs are designed with roller-type pilot bearings. All of the roller-type bearings available from Twin Disc are the separate race type, i.e. the inner race is removable from the outer race and seal assembly. Due to its design configuration, axial alignment of the inner and outer races is extremely important. The information and instructions below will assure proper bearing mounting. Instructions for assembly. Refer to the Twin Disc Power Take-Off Reference Listing in the Description and Specifications section, the exploded views in the Illustration section and Engineering Drawings near the back of this manual. Refer to information regarding cleaning and inspection in the Cleaning and Inspection section of this manual before proceeding. 1.



Position the pto on the bed of a press with the pilot bearing end up and the output end of the clutch shaft resting firmly on a solid support. Note: The PTO must be standing on the output end of the shaft.



The power take-off must be securely supported as it stands on the end of the shaft so it does not tip or fall over.



Use several 4” x 4” blocks or other means of insuring the PTO does not tip or fall over.



1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234



1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234



123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123



123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123



Output end of the shaft MUST rest and be in contact with a solid support (Press bed).



Figure 13. Support the pto standing on the end of the shaft



46



Power Take-Off Service Manual #1022764



Installation



Twin Disc, Incorporated



2.



Press the pilot bearing inner race on the clutch shaft so it is flush with the input end of the shaft.



3.



Carefully measure dimension (a). Record the measurement.



4.



Refer to the table in the Description and Specifications section of this manual. Subtract the appropriate roller bearing nominal width (c) from measurement (a). This will determine the position of the pilot bearing outer race in the flywheel bore (dimension b).



a - c = b (pilot bearing outer race position) 5.



Install the pilot bearing outer race in the flywheel and position it at dimension (b) as shown.



Pilot Bearing Inner Race



Inner race flush with end of shaft



Flywheel Housing Face



a Flywheel



b Pilot Bearing outer race



Figure 14. Install Pilot Bearing-Roller Type



Power Take-Off Service Manual #1022764



47



Installation



Twin Disc, Incorporated



PTO Installation to Engine or Driving Member Refer to the Twin Disc Power Take-Off Reference Listing in the Description and Specifications section, the exploded views in the Illustration section and Engineering Drawings near the back of this manual. Refer to information regarding cleaning and inspection in the Cleaning and Inspection section of this manual before proceeding. 1.



Clean the PTO housing flange, flywheel housing flange, and pilot bearing bore of any debris.



2.



Make sure the housing flange and flywheel housing flange are free of surface imperfections such as nicks, burrs, and sharp edges. Remove them using fine emery cloth or crocus cloth.



3.



Install a minimum of three guide studs in the flywheel housing, located approximately 120o apart. Using a suitable hoist, position the PTO on the guide studs and slide it against the flywheel housing, carefully aligning the pilot bearing with the pilot bearing bore in the flywheel and the teeth of the friction plates (6) with the drive ring (4).



Do not force the PTO unit onto the engine. If any resistance is noted, repeat the clutch plate centering procedure either in the clutch assembly or final assembly information of the Assembly section to align and center the friction plates so they mesh properly with the teeth of the drive ring. 4.



Secure the PTO housing to the flywheel housing with (12 or 16) hexhead capscrews. Torque the capscrew to the proper specifications given in Torque Values for Fasteners in the Description and Specifications section of this manual. Note: PTO housing to flywheel housing attachment screws must be grade 5 or better.



All except SP318SB models: (SP318SB skip to step 8) 5.



Rap the output end of the main shaft with a soft hammer to remove any preload on the main bearings and/or pilot bearing.



This step must not be omitted. Bearing failure may result. 48



Power Take-Off Service Manual #1022764



Installation



Twin Disc, Incorporated



6.



Measure the crankshaft endplay again. The measurement must be the same value as recorded from step 1 under Preliminary Checks. Locate and correct the source of preload if the endplay is not the same value.



Engine and/or PTO failure will result from any excessive preload on components. 7.



Install the key (34) on the output end of the clutch shaft (33) and install the drive sheave, chain sprocket, or u-joint flange as the application requires.



Refer to the Twin Disc Power Take-Off Reference Listing and Engineering Drawings towards the back of this manual. A customersupplied PTO support plate mounted at the output bearing retainer is to be used. Information about customer-supplied support plates is contained in Twin Disc PTO Support Plate Specifications in the Description and Specifications section of this manual.



SP318SB models: 8.



Remove three (only) of the capscrews (48) that attach the sheave housing (60) to the clutch housing (44). Remove three that are 120 degrees apart. Install three threaded guide pins in the holes to support the sheave housing as it is being removed.



9.



Remove the remaining capscrews (48) and remove the sheave housing.



10.



Install the sheave. Use a hydraulic power unit to properly position the sheave.



Be sure to install the power unit so the force is directed through the shaft and not across any of the bearings. The bearings may be damaged, resulting in premature failure.



The sheave must be aligned with the driven pulley. Align to within 1/2 of one degree using a straight edge or “tight-cord” method. Power Take-Off Service Manual #1022764



49



Installation



Twin Disc, Incorporated



11.



Again using the three dowel guide bolts, install the sheave housing. Be sure to orient it properly for the application. Install hex head capscrews in all but the three holes with dowel guide bolts.



The sheave housing must seat properly on the two dowel pins in the clutch housing. 12.



Remove the three guide dowels and replace with the remaining three hex head capscrews. Torque the capscrews to the proper specifications given in Torque Values for Fasteners in the Description and Specifications section of this manual.



Measure alignment of the sheave. 13.



Mount the dial indicator base on a secure location on the PTO housing. Position the tip of the dial indicator on the sheave as shown. Set the dial indicator to zero. Mount Dial Indicator Base Securely



Measure at Three Locations



Figure 15. Measure Sheave Alignment 14.



50



Rotate the sheave through one complete revolution and recheck accuracy with at least one other revolution. Read the total amount of dial indication sweep. Total runout must not exceed 0.254 mm. (0.010 in.) T.I.R. Mark the “high” spot as indicated when the dial indicator reaches its maximum progression point in the clockwise direction.



Power Take-Off Service Manual #1022764



Installation



Twin Disc, Incorporated



15.



Repeat at the other two locations as shown, marking the “high” spot of each. Total runout must not exceed 0.254 mm. (0.010 in.) T.I.R. Note: All three readings will normally be the same. If one is significantly different from the other two, first recheck to assure an accurate reading was obtained. If the readings exceed the allowable limit, alignment of the sheave must be corrected to prevent failure.



Install the belts. 16.



Remove the sheave housing as described above.



17.



Install the belts loosely in position in the grooves.



18.



Reinstall the sheave housing as described above.



19.



Install the support plate. Refer to support plate information in Twin Disc PTO Support Plate Specifications in the Description and Specifications section. Install six 1/2” x 13UNC-2A. Torque to 108 Nm. (80 lb.-ft.). Note: Verify proper shimming and alignment of the support plate.



20.



Tighten the belts to the manufacturer’s specifications, being sure that belt tension does not cause excessive deflection. (Refer to information in the Description and Specifications section and Installation Tips in this section to measure and assure that excessive deflection does not occur when the belts are tightened.)



21.



Install the hand lever assembly (53) and torque the hex head capscrew to the proper specifications given in Torque Values for Fasteners in the Description and Specifications section of this manual.



Power Take-Off Service Manual #1022764



51



Installation



Twin Disc, Incorporated



Hand Lever Position for Twin Disc Power Take-Offs Normal Position: Operating Shaft Horizontal To insure there is no preload on the shifting mechanism, the hand lever position with the clutch engaged should be slightly past vertical position, slightly towards engine.



The handle should NEVER be installed in a horizontal position when the operating shaft is positioned horizontally. Improper handle position can cause throwout collar failure resulting in catastrophic failure of the clutch. Vertical Engaged



Disengaged



Figure 16. Hand Lever Position



Special Position: Operating Shaft Vertical If the installation requires that the operating shaft be in a vertical position, a stop collar must be installed to prevent the weight of the hand lever, operating shaft and throwout yoke from creating a preload on the throwout collar. Position the hand lever as described above and also position and lock a stop collar on the operating shaft so that the throwout yoke is centered on the throwout collar. Contact Twin Disc’s Service Department for information on use of a stop collar. Operating Shaft



Stop Collar



Figure 17. Use of a stop collar with a vertical operating 52



Power Take-Off Service Manual #1022764



Installation



Twin Disc, Incorporated



Position and Measure Alignment of the Sheave 1.



Align the driveR and driveN shafts so that the faces of the sheaves are aligned and parallel to each other. Misalignment must be LESS THAN 1/2 of 1 degree between the faces.



2.



Position the sheave (driveR sheave on the PTO shaft) so it is aligned with the driveN sheave (on equipment being driven by the PTO).



3.



Calculate MAXIMUM allowable misalignment distance of the faces: Max. = 0.222 mm. (0.00875 in.) x distance between sheave centerlines.



4.



Place a tight cord or straight edge against both edges of the flat face of one sheave. Measure the distance between the cord or straight edge and the face of the other sheave. The gap is the misalignment distance. Align the sheaves to meet specifications.



Misalignment between the sheaves will result in shortened service life of the belts and may result in premature equipment failure.



Not Aligned



Aligned DriveR Sheave



Use Alignment straight edge or tight cord



DriveR Sheave



Straight edge or tight cord flat against both edges of one sheave



Straight edge or tight cord to be flat against both edges of both sheaves



DriveR and DriveN shafts must be parallel.



DriveN Sheave



Use Alignment straight edge or tight cord



DriveN Sheave



Misalignment Distance Measure misalignment distance between sheave face and cord or straight edge here.



Figure 18. Align Sheaves to Specifications Power Take-Off Service Manual #1022764



53



Installation



Twin Disc, Incorporated



Allowable Side Loads REAR OF BEARING HOUSING CENTERLINE OF SIDE LOAD x



L=



126,000 x H.P. x F x LF NxD



Figure 19. Allowable Side Pull and Formula to Determine Applied Load (See alternate illustrations for Spread Bearing Models) Formula values:




L = actual applied load (Lbs.)








N = shaft speed (RPM)








D = pitch diameter (in.) at sheave, etc.








F = load factor − 1.0 for chain or gear drive − 1.5 for timing belts








− −



2.5 for all V belts 3.5 for flat belts



LF = 2.1 for reciprocating compressors and other severe shock drivers and 1.8 for large inertia type drive (crushers, chippers, planers)



A support plate must be attached at the rear of the PTO if it is subjected to side load operation of the shaft. See the Twin Disc Power Take-Off Reference Listing and Support Plate Specifications in the Description and Specifications section of this manual. Note: SP318IL Power Take-offs are recommended for in-line, not side-loaded, applications.



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Table 15. Allowable Side Loads



(Table 15.1) SP218OP (M2713) (SP218P001, SP218P009) RPM 1000 1200 1800 2400



1 9099 8617 7631 7004



2 8701 8240 7297 6697



3 8336 7894 6991 6416



‘X’ Distance 4 5 6 8000 7407 6539 7596 7283 6539 6709 6450 6210 6158 5920 5699



7 5854 5854 5854 5854



8 9 5298 4839 5298 4839 5298 4839 5298 4839



1000 RPM



Maximum Load, Lbs.



Table 15.1 10000



1200 RPM



9000



1800 RPM



8000



2400 RPM



7000 6000 5000 4000 3000 2000 1000 0 0



2



4



6



8



10



"X" Distance, inches (see draw ing)



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Table 15. Allowable Side Loads (continued)



(Table 15.2) SP218OP (M2327) (SP218P002) ‘X’ Distance 4 5



RPM



1



2



3



1000 1200



9099 8617



8701 8240



7785 7785



6594 6594



1800



7631



7297



6991



2400



7004



6697



6416



6



7



8



9



5720 5720



5050 5050



4521 4521



4092 4092



3731 3731



6594



5720



5050



4521



4092



3731



6158



5531



5050



4521



4092



3731



1000 RPM



Table 15.2



Maximum Load, Lbs



1200 RPM



10000 9000 8000 7000 6000 5000 4000 3000 2000 1000 0



1800 RPM 2400 RPM



0



2



4



6



8



10



"X" Distance, Inches (See Sketch)



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Table 15. Allowable Side Loads (continued)



(Table 15.3) SP218OP (M2977) (SP218P003, SP218P008)



1000



1 9099



2 8701



3 8336



‘X’ Distance 4 5 6 8000 7690 7404



7 6937



8 6278



9 5734



1200 1800 2400



8617 7631 7004



8240 7297 6697



7894 6991 6416



7596 6709 6158



6760 5897 5494



6278 5799 5304



5734 5585 5126



RPM



7283 6450 5920



7012 6210 5699



Table 15.3



1000 RPM



Maximum Load, Lbs



1200 RPM 10000



1800 RPM



9000 8000



2400 RPM



7000 6000 5000 4000 3000 2000 1000 0 0



2



4 6 8 "X" Distance, Inches (See Sketch)



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Table 15. Allowable Side Loads (continued)



(Table 15.4) SP218OP (M1985A) (SP218P004)



1000 1200



1 8370 8370



2 6220 6220



3 5480 5480



‘X’ Distance 4 5 6 4665 4070 3600 4665 4070 3600



1800 2400



7631 7004



6220 6220



5480 5480



4665 4665



RPM



4070 4070



3600 3600



7 3230 3230



8 2930 2930



9 2690 2690



3230 3230



2930 2930



2690 2690



1000 RPM



Table 15.4



1200 RPM 9000



1800 RPM



Maximum Load, Lbs



8000



2400 RPM



7000 6000 5000 4000 3000 2000 1000 0 0



58



2



4 6 "X" Distance, Inches (See Sketch)



8



10



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Table 15. Allowable Side Loads (continued)



(Table 15.5) SP318P (M2977) (SP318P001, SP318P002, SP318P014) RPM



‘X’ Distance 5 6



1



2



3



4



1000



8000



7650



7340



7040



6790



1200 1800



7600 6620



7300 6350



7000 6080



6700 5840



6450 5620



7



8



9



6530



6110



5580



5100



6120 5400



6000 5220



5580 5030



5100 4710



1000 RPM



Maximum Load, Lbs



Table 15.5 9000



1200 RPM



8000



1800 RPM



7000 6000 5000 4000 3000 2000 1000 0 0



2



4 6 "X" Distance, Inches (See Sketch)



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Table 15. Allowable Side Loads (continued)



(Table 15.6) SP318P (M2713) ( SP318P004) RPM 1000 1200 1800



1 8000 7600 6620



2 7650 7300 6350



3 7340 7000 6080



‘X’ Distance 4 5 6 7040 6790 6000 6700 6450 6000 5840 5620 5400



7 5370 5370 5220



8 4870 4870 4870



Maxcimum Load, Lbs



Table 15.6



9 4450 4450 4450



1000 RPM



9000



1200 RPM



8000



1800 RPM



7000 6000 5000 4000 3000 2000 1000 0 0



60



2



4 6 "X" Distance, Inches (See Sketch)



8



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Table 15. Allowable Side Loads (continued)



(Table 15.7) SP318P (M2327) (SP318P005, SP318P009, SP318P010, SP318P013) RPM 1000 1200 1800



1 8000 7600 6620



2 7650 7300 6350



3 7340 7000 6080



4 6480 6700 5840



‘X’ Distance 5 6 5640 4990 5640 4990 5620 4990



7 4470 4470 4470



8 4050 4050 4050



1000 RPM



Table 15.7



Maximum Load, Inches



9 3700 3700 3700



9000



1200 RPM



8000



1800 RPM



7000 6000 5000 4000 3000 2000 1000 0 0



2



4



6



8



10



"X" Distance, Inches (See Sketch)



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Table 15. Allowable Side Loads (continued)



(Table 15.8) SP318SB (No Pilot Bearing) (SP318S001, SP318S002,SP318S004, SP318S005, SP318S006, SP318S007) RPM



5



6



‘X’ Distance 8 9



7



10



11



1000 1800



17900 19600 21800 22000 20700 18550 16800 15800 17400 19300 19700 18500 16600 15000



2100



15100 16600 18400 18800 17700 15900 14400



1200 RPM



Table 15.8



1800 RPM



Maximum Load, Lbs



25000



2100 RPM



20000 15000 10000 5000 0 4



5



6



7



8



9



10



11



12



"X" Distance, Inches (See Sketch below )



Rear Face of Housing (44) X



62



Centerline of Side Load



Power Take-Off Service Manual #1022764



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Table 15. Allowable Side Loads (continued)



(Table 15.9) SP321P (M2156B) (SP321P901, SP321P902, SP321P905) RPM 500 1000 1200 1500



1 2 3 12900 12400 11900 10250 9820 9450 9750 9350 9000 9200 8900 8500



‘X’ Distance 4 5 6 11100 9660 8550 9100 8750 8450 8650 8350 8050 8200 8000 7700



7 7600 7600 7600 7400



8 6950 6950 6950 6950



Table 15.9



9 6350 6350 6350 6350



500 RPM 1000 RPM



14000



1200 RPM



Maximum Load, Lbs



12000



1500 RPM



10000 8000 6000 4000 2000 0 0



2



4 6 8 "X" Distance, Inches (See Sketch)



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Alignment - U-Joint-Type Installation Refer to illustration on next page. To realize the longest possible life of the power take-off bearings, the best possible alignment must be maintained between the center line of the power take-off shaft and the center line of the driven unit shaft. 1.



It is extremely important that the forks of the drive shaft between the pto and the driven unit lie in the same plane. This will prevent severe vibrations from occurring in the drive shaft.



2.



The center lines of the pto shaft and the driven unit input shaft must be offset within the limits recommended by the u-joint manufacturer to prolong the life of the universal joint needle bearings.



3.



It is extremely important that the center lines of the pto shaft and driven unit input shaft be parallel. This will further prevent vibrations which cause premature pto bearing failure.



4.



Proper lubrication of the pto is important for satisfactory service. Refer to lubrication specifications in the Description and Specifications section of this manual.



Align the centerlines of the pto shaft and the input shaft of the driven unit. (One possible method is described below.)



64



5.



To align the engine and gear head by this method, two accurate straight edges at least 91 cm. (36 in.) long and a tape measure are required.



6.



Place the straight edges horizontally along the face of the pto and gear head hubs. Measure distances A and B. These two distances should be equal within 3.17 mm. (0.125 in.) at a point 45.7 cm. (18 in.) from the centerline of the shaft. Move the engine and/or driven unit to obtain this specification.



7.



Rotate the shafts so the straight edges are in a vertical position. Measure the distances C and D as was done for A and B in step 2. These two distances should be equal within 3.17 mm. (0.125 in.) at a point 45.7 cm. (18 in.) from the centerline of the shaft. Move the engine and/or driven unit to obtain this specification.



Power Take-Off Service Manual #1022764



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8.



Secure the engine and driven unit. Recheck A and B, C and D as described in steps 5 through 7 above. All measurements must be within the specifications. If not, repeat steps 5 through 7 until specifications are met.



Figure 20. Alignment - U-Joint-Type Installation



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Setting Up Air Engagement on Twin Disc Power Take Offs 1.



The cylinder should be located so that the piston moves forward and backward in exactly the same direction as the engagement lever and is aligned so it travels in exactly the same plane.



2.



The air cylinder must be of sufficient size to operate the required torque to engage the clutch. It must have some means to make adjustment on the piston stroke.



3.



Air pressure must be constant. Low pressures could give only partial engagement which will cause failures of the clutch and throwout collar.



4.



The piston travel must be within limits established to both fully engage and fully disengage the clutch. Failure to provide these parameters will cause failure and possible breakage of the clutch.



5.



The engaging cylinder must not place a pressure either in the engaged or disengaged direction after completion of its cycle. The throwout collar must float free after engagement or disengagement. Operating the pto with constant pressure on the throwout collar will result in failure. Suggestion: A slotted connector, similar to the one illustrated below may be used.



Adjust cylinder stroke so there is a clearance on both sides of the pin when in engaged AND disengaged positions



Fully Engaged Position



Fully Disengaged Position



Cylinder Rod



Connector with slotted hole Slotted hole Pin



Figure 21. Slotted Connector Used on Air Cylinder Rod



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6.



The air cylinder must be readjusted when the clutch is readjusted and any time the travel or position moves from the specifications described above.



Determine the length of travel for the engaging cylinder. 7.



Multiply the length of the hand lever by the value shown in the following chart. This provides the approximate required length of the piston stroke. Note: The hand lever length is the distance from the center of the operating shaft to the point where the cylinder will be connected to the lever. Table 16. Engaging Stroke Travel at 25.4 mm. (1 in.) Model



Engaging Stroke Travel at 25.4 mm. (1 in.) mm. inches



SP318P Series



8.890



0.350



SP318SB Series



8.890



0.350



SP318SB Series



8.941



0.352



Determine the engaging force in pounds required at the cylinder. 8.



Divide the force value in the chart below by the length of the hand lever (in inches). This provides the required force (in pounds) that must be provided by the piston. Note: Periodically disconnect the power cylinder to measure the clutch engagement force. Refer to Clutch Adjustment in the Maintenance section.



Table 17. Engaging Force Required at Cylinder at 25.4 mm. (1 in.) Model



Engaging Force Required in Cylinder Force (newtons) Force (pounds)



SP318P Series



32,783



7,370



SP318SB Series



32,783



7,370



SP318SB Series



32,783



7,370



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Operation



Operation



General Information Model SP218, SP318, SP318SB and SP321 Series Power Take-Offs consist of a manually engaged and disengaged disconnect clutch mounted on an output shaft in a cast iron housing that is bolted to the engine. Clutch engagement and disengagement is accomplished by means of an operating lever on the outside of the pto housing, which actuates an internal linkage mechanism. A drive ring is bolted to the engine flywheel. Internal teeth of the drive ring mesh with external teeth of the clutch driving plate(s). These are the input components of the Power Take-Off. Input components always rotate at engine rpm. Output components of the Power Take-Off consist of a clutch hub that is mounted on the output shaft, a linkage mechanism for clutch engagement and disengagement and clutch adjustment components. Clutches designed with multiple clutch driving plates have a clutch center plate located between the driving plates. The clutch center plate and pressure plate are driven through internal teeth that mesh with external teeth on the clutch hub. Until clutch engagement is initiated, the output components do not rotate. During clutch engagement, the clutch pressure plate is moved to clamp the clutch friction plate(s) against the friction face of the clutch hub (or the center plate(s). The internal engagement mechanism of the clutch locks the clutch pressure plate in the engaged position to complete the drive. Thus, at full clutch engagement while the engine is running, the output shaft is driven at engine speed. Grease- or oil-lubricated main bearings are located in the pto housing or bearing carrier. Some designs include a pilot bearing mounted in the engine flywheel to support the front end of the clutch shaft. However, some designs incorporate a main bearing configuration that does not require use of a pilot bearing. A support plate bolted to the bearing carrier is required to provide sufficient support where heavy weight and/or side loads exist.



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Clutch Engagement Procedure



Normal Clutch Engagement The PTO clutch should normally be engaged with the engine at the lowest rpm possible. The clutch should be engaged quickly to avoid an extended period of slippage during engagement. The clutch should be engaged with the engine operating below 1,000 rpm. After the clutch is fully engaged and the load has been brought up to engine engagement speed, the engine rpm may be increased to operating speed.



Clutch Engagement Where High Inertia Loads Exist Twin Disc, Inc. recommends that the PTO installation be designed to allow clutch engagement at 1,000 rpm or below. Under extreme circumstances, where high inertia loads must be picked up, the engine may have to be operated at higher speeds while the engagement occurs, as engaging the clutch at 1,000 rpm or below may result in stalling the engine.



Clutch engagement should occur at the lowest possible engine rpm. Heavy inertia loads may be brought up to engine speed by a series of short clutch engagements and disengagements at intervals long enough to gradually increase the speed of the load, yet prevent excessive heat buildup in the friction facings. After the clutch is fully engaged and the load has been brought up to engine engagement speed, the engine rpm may be increased to operating speed.



Under no circumstances should the clutch be slipped for more than a second or two without either fully engaging or disengaging the clutch to permit it to cool.



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Clutch engagement to clear a jammed driven device



Never engage the PTO to unjam a stuck load. Doing so could result in injury to the operator, and damage to the equipment. Always shut the engine off and disengage the clutch before clearing a jammed load. The jam should be cleared, and the output shaft must be rotated to be certain that the jam is completely removed before starting the engine and engaging the PTO.



Operator should be aware of the required clutch engagement force The clutch engagement force must be at the proper level to realize long life of the PTO clutch. If this engagement force seems low, refer to the Clutch Adjustment Procedure in the Maintenance section of this manual.



Insufficient clutch engagement force can cause clutch slippage resulting in catastrophic clutch failure. The engagement lever must be located in the proper position to prevent premature failures of the internal throwout collar components. The engagement lever should be in the vertical position with the clutch engaged. See Hand Lever Position for Twin Disc Power Take-Offs in the Installation section of this manual.



Improper handle position can cause throwout collar failure resulting in catastrophic failure of the clutch.



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NOTES



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Maintenance



Maintenance Tips Tapered Roller Bearing Adjustment 1.



Tapered roller bearing end play adjustment should have been adjusted prior to installation of the power take-off. Periodically check for excessive shaft movement during clutch engagement and disengagement and during operation to insure failure is not occurring. See information in the Installation section of this manual.



Pilot Bearings 2.



Ball-type pilot bearings and Roller-type pilot bearings must be installed properly. Some pilot bearings are to be greased periodically, See Lubrication this Maintenance section.



Lubrication 3.



Verify that the PTO is properly lubricated prior to starting the engine and at all times during operation. Refer to the Twin Disc Power Take-Off Reference Listing in the Description and Specifications section, Lubrication in this Maintenance section and Engineering Drawings near the back of this manual. Throwout bearing failures may be, among other causes, the result of improper lubrication.



Clutch Adjustment 4.



Check frequently to insure that the clutch is adjusted according to the procedure outlined in Clutch Adjustment in this Maintenance section. Failure to do so will result in premature clutch wear and failure. Note: Twin Disc will not be responsible for any damage or injury resulting from improper adjustment and/or lubrication. This includes any accessory drives and loads.



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Hand Lever Position 5.



Throwout bearing failures may be, among other causes, the result of improper hand lever position. See Hand Lever Adjustment for Twin Disc Power Take-Offs in the Installation section of this manual.



Alignment 6.



The flywheel and flywheel housing alignment should have been set within specifications prior to installation of the power take-off and must be maintained for long service life of the components. Misalignment of driven components can result in power take-off failure. Periodically check for bolts that may have loosened or driven components that have not been properly aligned during servicing or maintenance procedures. See information regarding Alignment in the Installation section of this manual.



Support Plate 7.



When mounting the engine and Power Take-Off in the machine, a customer-supplied support plate may be required to support the output end of the PTO housing. Proper installation and alignment of the support plate must be maintained. Periodically check to insure that the bolts securing the support plate are tightened to specifications and that the support plate is properly reinstalled and realigned whenever work is performed on the power take-off or power package module. See the information about customersupplied support plates and Twin Disc Support Plate Specifications contained in the Description and Specifications section of this manual.



Failure to follow maintain this requirement may result in damage to the power take off or the engine flywheel housing.



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Belt or chain tension/Allowable Side Load Pulls 8.



Maintain proper belt or chain tension adjustments. Avoid excessively tight or excessively loose belts or chains. Failure to maintain proper belt or chain adjustment can cause bearing failure and shortened power take-off service life.



Deflection Caused by Side Load Pulls 9.



Maintain proper side that do not exceed specified limits shown in Allowable Side Load Pulls in this Maintenance section and PTO Deflection in the Description and Specifications section.



Air Engagement Mechanisms 10.



Air engagement mechanisms remain properly adjusted at all times. See Setting Up Air Engagement on Twin Disc Power Take-Offs in the Installation section.



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Lubrication Refer to the Twin Disc Power Take-Off Reference Listing in the Description and Specifications section, the exploded views in the Illustration section and Engineering Drawings near the back of this manual.



Grease Specifications Use NLGI Grade 2 grease with a minimum 149° C. (300° F.) drop point for all lubrication.



Oil Specifications for oil-lubricated main bearings - SP218OP Series Use a good grade MS, DG, or better SAE No. 30 engine oil.



Lubrication Locations Config. A



Config. B



Collar (grease) Oil Level Check



Collar (grease)



Fill Main Bearings (oil)



Main Bearing (grease)



Operating Shaft (grease)



Operating Shaft (grease)



Drain



Config. D



Config. C Collar (grease)



Front Main Bearing (grease) Collar (grease)



Main Bearing (grease)



Operating Shaft (grease)



Output Bearing (grease)



Operating Shaft (grease)



Figure 22. Lubrication Locations



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Refer to the Twin Disc Power Take-Off Reference Listing in the Description and Specifications section, the exploded views in the Illustration section and Engineering Drawings near the back of this manual. Table 18. Quick-reference lubrication chart. Also see information above. Item Throwout Collars Main Bearings (Grease) Main Bearings (Oil) (SP218OP only)



Amount



Check Interval



Notes



1cc



Every 8-10 hrs.



NLGI Grade 2 Grease



Add 1cc



Every 8-10 hrs.



NLGI Grade 2 Grease



Fill to bottom of check plug hole.



Every 8-10 hrs. MS, DG or better Drain & fill SAE No. 30 Engine Oil 6 months/1000 hrs.



Operating Shaft



1cc



3 months/100 hrs.



NLGI Grade 2 Grease



Pilot bearings (Periodic lube)



1cc



3 months/100 hrs.



NLGI Grade 2 Grease



Pilot bearings (Pre-lubricated)



none required



Linkage



drop



500 hrs.



.



Main Bearings All Models SP318, SP318SB and SP321 Series (except models with purge plug (71) in the bottom of the bearing carrier) Apply 1 cc of grease (one shot from a grease gun) before start-up and then every 8-10 hours operation thereafter, through the fitting on the bearing carrier (55) or sheave housing.



All Models with grease lubrication and with a purge plug in bottom of bearing carrier: Some models (bearing housing Configuration B, for example) were designed with a plug (71) at the bottom of the bearing carrier to help purge the old grease from the cavity when new grease is added. Remove the purge plug before grease is added. Add grease through the grease fitting (51) until grease is visible in the open plug hole. Always rotate the shaft while adding grease to the bearing cavity. Run the PTO 1/2 hour until excess grease drains out. Then reinstall the plug. Note: Bearings will run hot if bearing cavity is overfilled. Power Take-off Service Manual #1022764



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Maintenance



Twin Disc, Incorporated



Models SP218OP Series The tapered roller bearings are lubricated from oil contained in an oil cavity in the bearing carrier. Fill through the oil fill fitting (72) until the oil level is at the proper level shown on the oil gauge. The oil level should be checked and maintained every 8-10 hours operation. Drain and refill the oil cavity every 6 months or 1000 hours (whichever occurs first).



Operating Shaft Fittings All Models SP218, SP318, SP318SB and SP321 Series Apply 1 cc. of grease (one shot from a grease gun) before starting and then every 3 months or 100 hours operation (whichever occurs first).



Throwout Collar All Models SP218, SP318, SP318SB and SP321 Series Apply 1 cc. of grease (one shot from a grease gun) daily before start-up and then every 8-10 hours operation thereafter, through the fitting on the tapered part of the housing.



Pilot Bearing All Models SP218, SP318, SP318SB and SP321 Series (except sealed-for-life style bearings). If the pilot bearing supplied with your power take-off is to be periodically lubricated, add one shot of grease from a grease gun every 100 hours through the fitting in the output end of the clutch shaft. Do Not Overgrease!!



All Models SP218, SP318, SP318SB and SP321 Series with sealedfor-life style bearings The pilot bearing supplied with most power take-offs is pre-lubricated and sealed for life. No maintenance is required. Inspection is recommended every two years or when the power take-off is removed from the driving component for servicing.



Clutch Linkage All Models Lubricate the clutch linkage mechanism, cotter pins, clevis pins and levers, with engine oil every 500 hours of operation.



Lubricate sufficiently but sparingly. Excess oil can splash or drip onto the friction plates, causing clutch slippage that may result in clutch failure. 78



Power Take-off Service Manual #1022764



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Twin Disc, Incorporated



Clutch Adjustment Note: New power take-offs must have clutch adjustment checked before being placed into service and after the first 10 hours of operation. This includes any power take-offs with new friction plates. New plates have a wear in period and the clutch may require several adjustments before the new plates are worn in. After wear in, clutch adjustment should be checked regularly. Heavy duty applications (rock crushers, etc.,) which have frequent engagements, numerous engagements in an operating day or relatively long periods of slip require more frequent readjustment than light duty applications. Adjust the clutch BEFORE it overheats, does not pull, or the operating lever jumps from the engaged position. But these symptoms are indications that clutch adjustment is required. Adjustment measurements are made by fitting a torque wrench with a 1 1/2” socket over the hex end located at the bottom of the hand lever. Grasp only the torque wrench when making measurements. 1.



Disconnect any power engagement devices from the operating shaft if so equipped.



To adjust the clutch: Refer to the exploded views in the Illustration section. 2.



Remove the instruction cover plate (45) from the housing (44) and turn the clutch shaft until the adjusting ring lock pin (25) can be reached.



3.



Disengage the adjusting lock pin and insert a cotter pin or small nail into the hole provided to hold it in the disengaged position. Turn the adjusting yoke (26) to the right (or clockwise when looking at the flywheel) until the required peak torque is required at the operating shaft (55) to engage the clutch. Refer to the Description and Specifications section of this manual for correct peak torque.



4.



Remove the cotter pin or small nail. Re-engage the adjusting ring lock pin.



5.



Repeat steps 3 and 4 above as necessary until the proper torque reading is obtained. Replace the instruction cover plate and secure with two hex-head capscrews (46). Securely tighten.



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Friction Plate Replacement Refer to the exploded views in the Illustrations section. Common symptoms indicating that the friction plates (6) are worn out are: 1.



The adjusting yoke (26) cannot be turned clockwise any further.



2.



The friction face surfaces have worn flush with the rivet heads, or the rivets are loose.



It is necessary to remove and disassemble the clutch assembly to replace the friction plates. Refer to instructions in the Disassembly and Assembly sections of this manual.



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Field Adjustment - Tapered Roller Bearings (side-loaded pto applications) (Except SB Models) Refer to the exploded views in the Illustrations section.



SP218 Series: The only approved method for field adjustment of tapered roller bearings (45 & 46) in Twin Disc Power Take-Off units is by the use of a dial indicator to read actual bearing end play.



All Models (except SP218 Series): There is no adjustment of ball-type or cylindrical roller-type bearings. Adjustment: Refer to the procedure in (Final Setting) Measure and Set Bearing End Play as described for your bearing housing configuration in the Assembly section of this manual. Refer to the illustration below and the Tapered Roller Bearing End Play setting for Tapered Roller Bearings used in Side-Load applications in the Description and Specifications section.



Dial indicator Use a Hoist and swivel hook.



Figure 23. Dial indicator and power take-off position for measuring and setting bearing end play. (Except SB Models)



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Checking Bearing End Play - Model SP318SB Series Only Refer to the Twin Disc Power Take-Off Reference Listing in the Description and Specifications section, the exploded views in the Illustration section and Engineering Drawings near the back of this manual.



Models SP318SB Series Only: There is no adjustment of SP318SB series bearings, but bearing end play should be verified to insure the bearings are not damaged or preloaded after work is done on the unit. Bearing end play must be 0.10 mm - 0.91 mm (.004 0.036 inches) after assembly. The only approved method for measuring bearing play in Twin Disc Power Take-Off units is by the use of a dial indicator to read actual bearing end play. 1.



Securely support the unit with the clutch shaft in a vertical position and the output end up. Be sure the shaft is clear to rotate.



Dial indicator Use a Hoist and swivel hook.



Figure 24. Dial indicator and power take-off position for measuring bearing end play. (SB Models) 82



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Twin Disc, Incorporated



2.



Attach an eyebolt in the thread at the output end of the shaft. Attach a hoist with a thrust bearing-equipped swivel hook to the eyebolt.



3.



Securely attach a dial indicator to the housing and locate the stem so the tip is contacting the end of the shaft and movement of the tip is exactly vertical, the same direction as the movement of the shaft.



4.



Lift the unit off the supports using the hoist. Apply approximately 90.7 Kg. (200 lbs.) of downward force on the bearing carrier while dial indicator is being set. Mark a spot on the end of the shaft next to the stem as a starting reference point and set the dial indicator to “zero.”



5.



Carefully and gently lower the unit back onto the supports. Allow the hoist to go slack. Apply approximately 90.7 Kg. (200 lbs.) of downward force on the shaft while dial indicator reading is being taken. (The weight of the shaft will be considered part of the 90.7 Kg. (200 lbs.) Read the dial indicator to read actual bearing end play.



6.



Repeat steps 4 and 5 to be sure the dial indicator reading repeats with accuracy. Bearing end play should be as shown above.



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Maintenance



Twin Disc, Incorporated



Bearing End Play - Tapered Roller Bearings used with In-Line Applications



SP218 Series: 1.



Field experience for tapered roller bearings used with in-line drive installations indicates that extra care must be taken when adjusting the power take-off tapered roller bearings.



2.



The end play for these applications is special for the above types of applications.



3.



Set bearing end play for these special applications using the method described for side-loaded applications on the previous pages, but set to the specifications shown in Tapered Roller Bearing End Play setting for Tapered Roller Bearings used in In-Line applications in the Description and Specifications section. Note: SP318P and SP321P Series: There is no adjustment of ball-type and roller-type main bearings. Note: SP318IL and SP318SB Series: Not designed for in-line applications.



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Power Take-off Service Manual #1022764



Disassembly



Twin Disc, Incorporated



Disassembly The following procedure is for complete disassembly of the unit. Prior to this procedure, the power take-off should be removed from the engine. Qualified personnel should do the work in a fully equipped facility. Note: Illustrations used here are to aid in understanding and completing the procedure, and may not appear to be consistent with the previous disassembly steps. Note: Four main bearing configurations are illustrated. Refer to the chart in the Description and Specifications section to determine which configuration is used in your pto.



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Disassembly



Twin Disc, Incorporated



Power Take-off Removal From The Engine Refer to the Twin Disc Power Take-Off Reference Listing in the Description and Specifications section, the exploded views in the Illustration section and Engineering Drawings near the back of this manual. 1.



Loosen and remove the belts and remove all attached parts from the output end of the power take-off.



2.



Remove the hex nut and hex-head capscrew securing the hand lever to the operating shaft.



3.



If used, loosen the support plate from the base mounting.



Configuration D only: (All other configurations skip to step 7.) 4.



Remove hex head capscrews (65) and washers (66) and remove the seal plate (64) from the sheave housing (60).



5.



Remove the hex head capscrews (48) and remove the sheave housing. Bearing (41) will also be removed with the sheave housing.



6.



Remove the belts.



All Configurations: 7.



Attach lifting equipment to the power take-off and take out the slack just enough to begin to support the weight of the pto. Do not apply too much force.



Lifting devices and their capacity must be capable of supporting the weight of the power take-off and all attached devices and equipment. Suspend the pto with the lifting devices securely attached at 3 positions (minimum) so it remains with the main drive shaft in a horizontal position until it is safely lowered and resting on a secure bed.



86



8.



Remove the sixteen hex-head capscrews securing the power take-off to the engine flywheel housing. Use two 1/2”-13 UNC x 1 1/2” bolts as pusher screws in the two tapped holes provided in the housing flange. Use the pusher screws to separate the pto from the engine flywheel housing. Remove the power take-off from the engine.



9.



Remove the (six or twelve) hex-head capscrews securing the drive ring to the engine flywheel. Power Take-off Service Manual #1022764



Disassembly



Twin Disc, Incorporated



Clutch Removal Refer to the Twin Disc Power Take-Off Reference Listing in the Description and Specifications section, the exploded views in the Illustration section and Engineering Drawings near the back of this manual. 1.



Support the power take-off on a bench with the clutch end facing up. Use wooden blocks under the power take-off.



2.



If the pilot bearing (or pilot bearing inner race) remained on the shaft, remove it using a standard bearing puller.



3.



If the pilot bearing is a two-piece bearing, remove the bearing’s outer race from the flywheel using a standard bearing puller. Note: The pilot bearing will be destroyed upon removal. If the bearing seal is broken the bearing is considered destroyed.



4.



Remove the two hex- head capscrews and remove the instruction plate if they were not previously removed.



5.



Use a 15/16” wrench to remove the jam nut and lock washer from the hose fitting located on the side of the power take-off housing. Push the fitting and hose into the power take-off housing.



6.



Straighten the bent portion of the hub nut lock washer. Use a 4” wrench or socket to remove the hub nut from the clutch shaft. Remove the hub nut lock washer.



7.



Use a gear puller with threaded legs for 3/4”-10 UNC tapped holes to pull the clutch assembly from the clutch shaft. Install the puller so the threaded legs screw into the holes provided in the hub-and-back plate and the jackscrew exerts force on the end of the clutch shaft.



The thread puller holes are not to be used as jackscrews. Remove the clutch and puller from the clutch shaft. Remove the hub key if it was not removed with the clutch.



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Disassembly



Twin Disc, Incorporated



Clutch Disassembly Refer to the Twin Disc Power Take-Off Reference Listing in the Description and Specifications section, the exploded views in the Illustration section and Engineering Drawings near the back of this manual.



All 18 inch model clutches 1.



Set the clutch assembly on a bench with the throwout collar facing up. Disengage the clutch.



2.



Remove the grease fitting (23) from the hose fitting (20). Remove the hose (19) and hose fitting (18) from the trunnion of the collar assembly.



3.



Remove the four cotter pins (17) from the four clevis pins (16) securing the sliding sleeve to the links (15).



4.



Remove the sleeve and collar assembly from the links.



Bronze Collar Disassembly 5.



Remove two hex huts and two hex head bolts to remove the throwout collar halves and shims from the sliding sleeve.



Ball Bearing Collar Disassembly



88



6.



If the unit has a grease shield (73), use a large flat screwdriver to pry it from the collar (28).



7.



Remove the internal snap ring (31) from the collar.



8.



Remove the external snap ring (29) from the sliding sleeve (27).



9.



Press the sleeve from the bearing and collar in a press or pull the bearing from the sleeve.



10.



Remove the snap ring (29) from the sleeve.



Power Take-off Service Manual #1022764



Disassembly



Twin Disc, Incorporated



All 18 inch model clutches 11.



Pull the adjusting lock pin (25), compressing the lock pin spring (24), and unscrew the adjusting ring (26) from the hub-and-back plate assembly. Remove the adjusting lock pin and spring from the adjusting ring.



12.



Straighten and remove the four cotter pins (13) and the four clevis pins (14) to disconnect the eight links from the four levers (9).



13.



Straighten and remove the four cotter pins (12), four washers (10) and four clevis pins (11) that secure the levers to the pressure plate (8). Remove four levers from the pressure plate.



14.



Remove the pressure plate and friction plate (6) from the hub-and-back plate (4).



15.



Remove the top friction plate (6) and center plate (7) from the hub-andback plate.



Three- plate 18 inch model clutches only 16.



Remove the remaining friction plate (6) and center plate (7) from the hub-and-back plate.



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Disassembly



Twin Disc, Incorporated



Remove the Operating Shaft and Throwout Yoke Refer to the Twin Disc Power Take-Off Reference Listing in the Description and Specifications section, the exploded views in the Illustration section and Engineering Drawings near the back of this manual.



All SP218, SP318, SP318SB and SP321 Series 1.



Remove the hex-head capscrew from the throwout yoke (54). Tap one end of the operating shaft (55) gently to expose one of the woodruff keys (56). Remove the key. Do the same for the other side of the shaft to remove the other key. Remove the operating shaft from the clutch housing (44) and throwout yoke.



2.



Remove the two grease fittings (57) from the outside of the housing near the operating shaft holes only if replacement of the parts is necessary.



Proceed to Clutch Shaft and Housing Disassembly: Four main bearing configurations are illustrated. Refer to the Twin Disc Power Take-Off Reference Listing in the Description and Specifications section to determine which configuration is used in your PTO. Skip to: Clutch Shaft and Housing Disassembly - Configuration A Clutch Shaft and Housing Disassembly - Configuration B Clutch Shaft and Housing Disassembly - Configuration C Clutch Shaft and Housing Disassembly - Configuration D



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Power Take-off Service Manual #1022764



Disassembly



Twin Disc, Incorporated



Clutch Shaft and Housing Disassembly - Configuration A Refer to the BOM and exploded views in the Illustrations section of this manual and the main bearing housing configuration below.



Figure 25. Illustration - Configuration A



1.



Remove the oil gauge (66) from the oil gauge tube (67) in the bearing carrier (47).



2.



Turn the power take-off housing with attached parts over on the bench. Support the housing so the output end of the clutch shaft faces up and is free to rotate. There should be a clearance below the input end of the clutch shaft.



3.



Remove the oil gauge tube from the bearing carrier only if replacement of either is necessary.



4.



Remove hex head capscrews (48) and remove the support plate if used.



5.



Lift the clutch shaft (33) and bearing carrier (47) unit from the clutch housing (44). Remove and discard the rubber seal (58) located at the bearing carrier pilot.



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Disassembly



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Twin Disc, Incorporated



6.



Secure the clutch shaft with attached parts in a large vise with protective jaws, with the input end of the shaft facing up, gripping the rear cast section of the bearing carrier in the vise.



7.



Remove the oil slinger (43) from the shaft using a gear puller.



8.



Remove the six capscrews (35), three locking plates (36), bearing retainer (38) and shims (63).



9.



Lift the clutch shaft with bearing cones (40 & 41) and wear sleeve (69) from the bearing carrier. The forward bearing cup (39) will come out with the shaft and bearing cones.



10.



Use an arbor press or bearing puller to remove the bearing cones from the clutch shaft. The bearing cones remove in opposite directions from the shoulder machined on the clutch shaft. The wear sleeve will be removed when the cones are removed.



11.



Remove the rear bearing cup from the bearing carrier by removing the two 1/8 pipe plugs (52) from the bearing carrier and tapping the bearing race (42) from the bearing carrier through the holes using a blunt punch.



12.



Knock the oil seal (70) out of the bearing carrier (47).



13.



Lay the clutch housing on its side and tap out the oil seal (68) using a blunt-end punch.



14.



Remove the fill fitting (72) and drain plug (71) from the bearing carrier.



Power Take-off Service Manual #1022764



Disassembly



Twin Disc, Incorporated



Clutch Shaft and Housing Disassembly - Configuration B Refer to the BOM and exploded views in the Illustrations section of this manual and the main bearing housing configuration below.



Figure 26. Illustration - Configuration B



1.



Turn the power take-off housing with attached parts over on the bench. Support the housing so the output end of the clutch shaft faces up and is free to rotate. There should be a clearance below the input end of the clutch shaft.



2.



Remove hex head capscrews (48) and washers (49) and remove the support plate if not previously removed.



3.



Lift the clutch shaft (33) with the main bearing (40) and bearing carrier (47) from the main housing (44).



4.



Secure the bearing carrier with attached parts in a large vise with protective jaws, with the input end of the shaft facing up, gripping the rear cast section of the bearing carrier in the vise.



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Disassembly



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Twin Disc, Incorporated



5.



Remove the six hex head capscrews (35) and washers (36) that secure the bearing retainer (38) to the bearing carrier. Remove the bearing retainer.



6.



Remove the shaft and bearing from the bearing carrier (47). If necessary, the bearing carrier may be gently tapped off the bearing.



7.



Remove the external snap ring (59) from the shaft.



8.



Use an arbor press to press the shaft out of the bearing (40).



9.



Remove the grease fitting (51) and purge plug (71) (if used) from the bearing carrier.



10.



Remove two capscrews (74) and bottom plate (62) from the clutch housing (44).



Power Take-off Service Manual #1022764



Disassembly



Twin Disc, Incorporated



Clutch Shaft and Housing Disassembly - Configuration C Refer to the BOM and exploded views in the Illustrations section of this manual and the main bearing housing configuration below.



Figure 27. Illustration - Configuration C 1.



Turn the power take-off housing with attached parts over on the bench. Support the housing so the output end of the clutch shaft faces up and is free to rotate. There should be a clearance below the input end of the clutch shaft.



2.



Remove hex head capscrews (48) and washers (49) and remove the support plate if used.



3.



Lift the clutch shaft (33) and bearing carrier (47) unit from the clutch housing (44).



4.



Secure the bearing carrier with attached parts in a large vise with protective jaws, with the input end of the shaft facing up, gripping the rear cast section of the bearing carrier in the vise.



5.



Remove the six hex head capscrews (35) and washers (36) that secure the bearing retainer (38) to the bearing carrier.



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Disassembly



96



Twin Disc, Incorporated



6.



Remove the shaft (33) with the main bearings (40 and 41) from the bearing carrier (47). If necessary, the bearing carrier may be gently tapped off the bearings.



7.



Use an arbor press to press the shaft out of the bearings (40 and 41). The bearings remove in opposite directions from the shaft shoulder.



8.



Remove the grease fitting (51) from the bearing carrier.



9.



Remove two capscrews (74) and bottom plate (62) from the clutch housing (44).



Power Take-off Service Manual #1022764



Disassembly



Twin Disc, Incorporated



Clutch Shaft and Housing Disassembly - Configuration D Refer to the BOM and exploded views in the Illustrations section of this manual and the main bearing housing configuration below.



Figure 28. Illustration - Configuration D 1.



Remove the hex head capscrews and remove the support plate if it was not previously removed.



2.



Securely support the pto so the output end of the clutch shaft faces up and is free to rotate. There should be a clearance below the input end of the clutch shaft.



3.



Remove four capscrews (76) and the cover (75) from the bearing retainer (64) if not previously removed.



4.



Remove the hex head capscrews (65) and remove the rear bearing retainer (64) from the sheave housing if not previously removed.



5.



Remove the hex head capscrews (48) that secure the sheave housing (60) to the clutch housing (44) and remove the sheave housing if not previously removed. Note: The inner race of bearing (41) will remain on the shaft.



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Disassembly



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Twin Disc, Incorporated



6.



Remove the sheave from the shaft.



7.



Remove the outer race of bearing (41) from the sheave housing if not previously removed.



8.



Remove the fitting (50) from the bearing retainer.



9.



Remove the twelve hex head capscrews (35) and remove the front bearing retainer (38) from the clutch housing (44).



10.



Lift the clutch shaft (33) with the inner races of the front and rear bearings (40 & 41) from the clutch housing.



11.



Remove the outer race of the rear bearing (40) from the main housing.



12.



Using a split-type bearing puller, remove the inner race of the rear bearing (41) from the shaft.



13



Using a split-type bearing puller, remove the inner race of the front bearing (40) from the shaft.



Power Take-off Service Manual #1022764



Cleaning and Inspection



Twin Disc, Incorporated



Cleaning and Inspection



Cleaning and Inspection Refer to the BOM and exploded views in the Illustrations section and the Engineering Drawings near the back of this manual.



Bearings 1.



Thoroughly wash bearings in clean solvent if they have been in service. Soak bearings in solvent if they are particularly dirty.



Never dry bearing with compressed air. Do not spin bearings while they are not lubricated. Oil bearings with SAE 10 engine oil immediately after cleaning. Be sure bearings are oiled before inspection. Protect clean bearings, whether they are new or have been in service, from dirt, dust, grit or any other contaminant. 2.



Inspect bearings for roughness of rotation. Replace the bearing if roughness is found.



3.



Inspect bearings for corrosion, scored, scratched, cracked, pitted or chipped races, and for indication of excessive wear of balls or rollers. If one of the these defects is found, replace the bearing.



Preventing Entrance of Dirt Into Bearings 4.



Dirt and grit in bearings are often responsible for bearing failure. Consequently, it is important to keep bearings clean. Do not remove grease from new bearings. Keep the wrapper on new bearings until immediately before they are to be installed. Do not expose new clean bearings until they are ready to be used in the assembly. Keep them wrapped in clean lint-free cloth or paper to keep out dust and debris. Protect bearings from contamination even after they are installed on the shaft or in the bore.



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Cleaning and Inspection



Twin Disc, Incorporated



Housings, Cast Parts and Machined Surfaces 5.



Replace cast parts or housings that are cracked.



6.



Inspect bearing bores for grooved, burred or galled conditions that would indicate that the bearing has been turning in its housing. If the damage cannot be repaired to like-new condition with a crocus cloth, replace the part. Bore diameters must not exceed the maximum dimension shown in Wear Limits the Description and Specifications section of this manual. Closely check bearing bore for damage. Check threads or pilot for damage. Check face for damage.



Typical Bearing Carrier or Housing bore area



Figure 29. Inspect the bores, threads and faces 7.



Inspect bores for wear, grooves, scratches and dirt. Remove burrs and scratches with crocus cloth or a soft stone. Replace parts that are deeply grooved or scratched.



8.



Inspect oil and grease passages for obstructions. If an obstruction is found, remove it with compressed air or by working a wire or wire brush back and forth through the passage and flushing it with solvent. brush back and forth through the passage and flushing it with solvent.



All grease and oil passageways must be clean.



Figure 30. Be sure passageways are clean. 100



Power Take-off Service Manual #1022764



Cleaning and Inspection



Twin Disc, Incorporated



Shafts, seal lip contact surfaces and bearing journals 9.



Inspect machined surfaces for burrs, scratches, nicks and foreign matter. If such defects cannot be removed with crocus cloth or a soft stone, replace the part.



10.



Inspect bearing journals on the shaft for grooved, burred or galled conditions that would indicate that the bearing has been turning on the shaft. If the damage cannot be repaired to like-new condition with a crocus cloth, replace the part. Bearing journal diameters must not be less than the dimensions shown in Wear Limits the Description and Specifications section of this manual.



11.



Inspect the pilot bearing journal on the clutch shaft. If it is worn in any way, or if it shows signs that the pilot bearing has been turning on the journal, replace the clutch shaft. Pilot bearing journal diameters must not be less than the dimensions shown in Wear Limits the Description and Specifications section of this manual. Pilot Bearing Journal



Main Bearing Journal A (and seal journal)



1 Main Bearing Journal B (and seal journal)



Pilot Bearing Journal



Main Bearing Journal A



2



Main Bearing Journal A



3



Main Bearing Journal B Main Bearing Journal A



4 Main Bearing Journal B



Figure 31. Inspect bearing journals and seal journals Power Take-off Service Manual #1022764



101



Cleaning and Inspection



Twin Disc, Incorporated



12.



Inspect seal journal surfaces on the shaft. Look especially for scratches or nicks that extend above the shaft surface. If they cannot be removed using a fine crocus cloth, replace the part. Seal journal diameters must not be less than the dimensions shown in Wear Limits the Description and Specifications section of this manual.



13.



Inspect seal lip contact surfaces on wear sleeves and other surfaces. Look especially for scratches or nicks that intersect with or cross the lip contact area. If they cannot be removed using a very fine crocus cloth, replace the part.



14.



Inspect threaded openings for damaged threads. Chase damaged threads with a tap of the correct size.



15.



Be sure the snap ring grooves have straight sides, especially if a bearing failure has occurred.



Straight sides



Damaged Wall



Undamaged Groove



Damaged Groove



Figure 32. Snap ring grooves must have square sides



102



Power Take-off Service Manual #1022764



Assembly



Twin Disc, Incorporated



Assembly The following procedure is for complete assembly of the unit. Prior to this procedure, the power take-off should be removed from the engine. Qualified personnel should do the work in a fully equipped facility. Note: Illustrations used here are to aid in understanding and completing the procedure, and may not appear to be consistent with the previous assembly steps. Note: Four main bearing configurations are illustrated. Refer to the Twin Disc Power Take-Off Reference Listing in the Description and Specifications section to determine which configuration is used in your pto.



Power Take-off Service Manual #1022764



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Assembly



Twin Disc, Incorporated



Clutch Assembly Refer to the Twin Disc Power Take-Off Reference Listing in the Description and Specifications section, the exploded views in the Illustration section and Engineering Drawings near the back of this manual.



Bronze Throwout Collar only: (Ball Bearing Type Throwout Collar skip to step 3.) 1.



Lubricate the shoulder of the sliding sleeve (27) with No. 30 engine oil prior to installation of the split collar. Place the throwout collar halves over the sliding sleeve shoulder. Install 2 hex head capscrews 1/2” - 20 x 3 1/4” through the halves. Install 2 hex nuts on the capscrews. Torque the capscrews to the proper specifications given in Torque Values for Fasteners in the Description and Specifications section.



Sliding Sleeve



18 Capscrew 19 20 Collar Halves



23



22



21



Nut



Figure 33. Assembly of Bronze Throwout Collar



2.



104



Check collar rotation to be sure it turns freely on the sliding sleeve. (Proceed at step 8.)



Power Take-off Service Manual #1022764



Assembly



Twin Disc, Incorporated



Ball Bearing Type Throwout Collar 3.



Press the ball bearing (30) in the throwout collar (28). Press the bearing to the bottom of the bore. Note: Pack the bearing with grease before installing it on the collar. Note: Apply force only against the outer race of the bearing. Pressing against the inner race or contact with the balls will damage the bearing, leading to premature failure.



Figure 34. Assembly of Ball Bearing Type Throwout Collar



4.



Install the internal snap ring (31) in the collar.



5.



Place the sliding sleeve (27) on the bed of a press with the bearing end up. Press the bearing and collar on the sliding sleeve. The internal snap ring (31) must be up and the top of the bearing must clear the snap ring groove on the sliding sleeve. Note: Apply force only against the inner race of the bearing. Pressing against the outer race or contact with the balls will damage the bearing, leading to premature failure.



6.



Install the external snap ring (29) to secure the bearing on the sliding sleeve.



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Assembly



Twin Disc, Incorporated



7.



Support beneath the collar on the press bed. Press the sleeve down until the bearing’s inner race is tight against the external snap ring.



Excessive pressure or sharp impact against the outer race of the bearing during installation of the collar will damage the bearing, leading to premature failure.



SP318 and SP318SB Series with Grease Shield only: (SP218 Series with Ball Bearing Type Throwout Collar skip to step 9.) 8.



Be sure the collar is still supported on the bed of a press with the internal and external snap rings up, and with the supports under the collar, not the sliding sleeve. Press the grease shield (73) into the collar, snug against the snap rings.



Assemble the plate stack SP218, SP318, SP318SB and SP321 Series: 9.



Set the hub and back plate (4) on a bench with the threaded and splined section facing up.



10.



Install a friction plate (6) on the hub-and-backplate.



Figure 35. Typical SP218, SP318, SP318SB and SP321 Plate Stack (SP318 Series is shown) 106



Power Take-off Service Manual #1022764



Assembly



Twin Disc, Incorporated



11.



Install a center plate (7) so it rests flat on the friction plate, meshing the splines of the center plate and hub-and-backplate.



12.



Install a second friction plate (6) on the center plate.



SP318, SP318SB and SP321 Series clutches only: (SP218 skip to step 15.) 13.



Install a second center plate (7) so it rests flat on the second friction plate, meshing the splines of the center plate and hub-and-backplate.



14.



Install a third friction plate (6) on the second center plate assembly.



SP218, SP318, SP318SB and SP321 Series clutches: 15.



Install the pressure plate (8) on the top friction plate, meshing the splines of the center plate and hub-and-backplate.



16.



Install the adjusting lock pin spring (24) into the pocket in the pressure plate and install the adjusting lock pin (25) on the spring.



Figure 36. Illustration - Levers, Links, Sleeve, Throwout Collar



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Assembly



Twin Disc, Incorporated



17.



Push down on the pin, compressing the spring while screwing the adjusting yoke (26) partially onto the threaded part of the hub-and-back plate.



18.



Place the levers (9) between the lugs of the pressure plate and secure to the pressure plate with four clevis pins (11). Note: Hook each lever under the edge of the adjusting yoke while aligning the clevis pin hole with the holes in the pressure plate lugs.



19.



Place a washer (10) on each clevis pin and install four cotter pins (12). Spread the legs of the cotter pins as shown below.



Legs do not extend outside this area.



25.4 mm. (1.00 in.) Diameter (12) 31.0 mm. (1.22 in.) Diameter (13 & 17)



12.7 mm. (0.50 in.) Radius (12) 15.5 mm. (0.61”) Radius (13 & 17)



Figure 37. Spread the cotter pin legs



108



20.



Attach eight lever links (15) one on each side of each of the four clutch levers (9). Secure with four clevis pins (14) and four cotter pins (13).



21.



Place the pre-assembled sliding sleeve (27) on the adjusting yoke, aligning the four lugs between the four pairs of lever links.



22.



Attach the links to the sliding sleeve with four clevis pins (16) and four cotter pins (17).



23.



Install the hose fitting (18) in the collar trunnion, and attach the flexible hose (19), hose fitting (20) and lubrication fitting (23).



Power Take-off Service Manual #1022764



Assembly



Twin Disc, Incorporated



Center the clutch plates 24.



Visually center the friction plates (6) on the clutch and align the teeth. Press down on the collar assembly to lock the plates in place. If necessary, pull the adjustment lock pin to compress the lock pin spring, and rotate the adjusting yoke assembly until the plates are locked in position when the collar is pressed down. Note: This is an initial setting to hold the plates in place until after the pto is mounted on the engine, so it is imperative that the teeth be exactly aligned and the plates are exactly centered on the clutch. The driving ring may be used as an alignment fixture to align the teeth and center the plates relative to the hub-and-backplate so they are perfectly aligned when the pto is installed on the engine. Perfectly center the clutch in the drive ring. (This gap is to be exactly equal all the way around.)



Driving Ring (1) Teeth Wooden block (use 3) to hold driving ring in position



Bench



Figure 38. Align the Plate Stack



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Assembly



Twin Disc, Incorporated



Proceed to Clutch Shaft and Housing Assembly: Four main bearing configurations are illustrated. Refer to the Twin Disc Power Take-Off Reference Listing in the Description and Specifications section to determine which configuration is used in your PTO. Skip to: Clutch Shaft and Housing Assembly - Configuration A Clutch Shaft and Housing Assembly - Configuration B Clutch Shaft and Housing Assembly - Configuration C Clutch Shaft and Housing Assembly - Configuration D



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Assembly



Twin Disc, Incorporated



Clutch Shaft and Housing Assembly - Configuration A Refer to the Twin Disc Power Take-Off Reference Listing in the Description and Specifications section, the exploded views in the Illustration section and Engineering Drawings near the back of this manual.



Figure 39. Illustration - Configuration A



Clutch Shaft 1.



Clean the tapered bearing cones (40 & 41) and clutch shaft (33) with isopropyl solvent to remove any oil or grease residue. Note: Do not use any oil or paraffin based solvents.



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Twin Disc, Incorporated



2.



Use an arbor press to install the two bearing cones on the clutch shaft. Install the cones, one from each end, with the back faces (wide section) butting against the shoulder on the clutch shaft. Use a piece of steel tubing approximately 5 cm. (2 inches) longer than the distance from the end of the shaft to the shoulder and just slightly larger in inside diameter than the bearing cone’s inside diameter. The tubing must not be thick enough to contact the cage of the bearing during installation.



Press Ram



Note: I.D. of Press Tube is slightly larger than the I.D. of the bearing.



Flat Plate (tool) Press Tube



Note: Thickness of Press Tube wall must contact ONLY the inner race of the bearing.



Bearing Cone (41)



Output end of Clutch Shaft (33)



Note: Bearing must be pressed tight against the shoulder.



Figure 40. Install bearing cones on the shaft



Note: An alternative method to install the bearing cones is to heat them in an oven at 135° C. (275° F.) for one hour and install them immediately on the clutch shaft. Let the bearing cones cool to room temperature after installation. Continue to apply force as the bearing cools to room temperature ensuring that it remains seated.



Handle the heated parts with care. The heated parts are extremely HOT.



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Assembly



Twin Disc, Incorporated



3.



Coat the I.D. of the rear wear sleeve (69) with an anaerobic sealant Twin Disc part number M2828. Press the sleeve onto the shaft. The flat end of the sleeve should be nearest the rear bearing cone. When positioned properly, the contoured side will align exactly with the shoulder of the shaft. Be sure the contour blends in with the shoulder of the clutch shaft. Remove excess sealant when sleeve is in its proper position on the shaft. Contour is flush. Wear sleeve



Shaft wear sleeve shoulder



Shaft shoulder



Figure 41. Locating the oil seal wear sleeve on the shaft Note: The front wear sleeve (63) will be installed on the shaft later in the assembly procedure. It will be installed after final bearing end play is set and the oil slinger is then installed.



Clutch housing 4.



Set the clutch housing (44) on the bed of a press with the input end of the housing facing down.



5.



Install 2 lubrication fittings (57) if they were removed.



6.



Rest the front oil seal (68) in the housing bore; the seal lip should be up, extending toward the bearing carrier. Use a flat steel plate slightly larger in diameter than the O.D. of the oil seal. Press the seal straight into the bore until the steel plate stops against the surface of the housing. The top end of the outer shell of the seal should be flush with the surface of the housing. Pre-lubricate the seal lip with clean No. 30 engine oil. Note: Press only on the outer shell of the seal. Do not damage the seal lip.



7.



Set the clutch housing on a work bench, securely supported with wooden blocks, with the input end of the housing facing down. There should be sufficient clearance below the housing to allow for installation of the clutch shaft.



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Bearing Carrier 8.



Position the bearing carrier (47) on the bed of an arbor press with the input end down.



9.



Rest the rear oil seal (70) in the bore; the seal lip should be down, extending toward the input end of the bearing carrier. Use a flat steel plate slightly larger in diameter than the O.D. of the oil seal. Press the seal straight into the bore until the steel plate stops against the surface of the carrier. The rear of the outer shell of the seal should be flush with the surface. Pre-lubricate the seal lip with clean No. 30 engine oil. Note: Press only on the outer shell of the seal. Do not damage the seal lip.



10.



Invert the bearing carrier (47) on the bench so the input end is up. Use a piece of steel tubing or round plate slightly smaller in diameter than the outer diameter of the rear main bearing cup. Place the bearing cup (41) on the carrier, back face down. Be sure the steel tubing or plate does not press against the bearing contact surface in the cup. Press the cup to the bottom of the bore. Press Ram Flat Plate (tool) Scrap Bearing Cup used upside down New Bearing Cup (42)



Press bearing cup to bottom of the bore.



Bearing Carrier (47)



Figure 42. Install the rear bearing cup (41)



114



11.



Pre-lubricate the wear sleeve surface with clean No. 30 engine oil in preparation for installation of the shaft into the bearing retainer.



12.



Coat the bearing rollers and both bearing cups with a light film of clean No. 30 engine oil.



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Install the clutch shaft and bearing cones into the bearing carrier. 13.



Place the bearing carrier (47) in a large bench vise with protective jaws or securely support it on a bench with the input end up. There must be sufficient clearance below the carrier to install the shaft. Carefully install shaft and bearings in the bearing carrier. Be careful to not damage the seal lip as the shaft is installed through it.



14.



Install the forward bearing cup (39) into the bearing carrier.



15.



Install the bearing retainer (38) over the clutch shaft, resting against the bearing cup.



(Preliminary setting) Measure and set bearing end play 16.



Use 3 of the 6 hex head capscrews (35) and pull the retainer down evenly until 6.8 Nm. (60 in.-lbs.) of torque is required to rotate the shaft. Note: Do not overtighten! Damage may occur to the bearings or bearing retainer. Rotate the shaft several revolutions. This aligns and seats the bearing cones in the bearing cups and creates a “zero” clearance.



17.



Measure the shim gap between the bearing retainer and the bearing carrier with a feeler gage. Add a thickness of shims equal to the gap plus 0.15 - 0.25 mm. (0.006 - 0.010 in.). Note: For in-line operation, add a thickness of shims equal to the gap plus 0.23 - 0.30 mm. (0.009 - 0.012 in.).



18.



Remove the three hex head capscrews and the bearing retainer. Install the selected shim pack (37) and reinstall the retainer, 6 hex head capscrews (35) and three lock plates (36). Torque the capscrews to the proper specifications given in Torque Values for Fasteners in the Description and Specifications section. Note: Bump the output end of the shaft with a soft mallet hard enough to move and seat the front bearing cup up against the bearing retainer and create the specified bearing clearance.



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(Final setting) Measure and set bearing end play 19.



Securely support the unit with the clutch shaft in a vertical position and the output end up. Be sure the shaft is clear to rotate.



Dial indicator Use a Hoist and swivel hook.



Note: Typical housing configuration is illustrated. Your housing may be designed differently.



Shims Bearing Retainer



Figure 43. Measuring and setting bearing end play



116



20.



Attach an eyebolt in the 5/8”-11 thread at the output end of the shaft. Attach a hoist with a thrust-bearing-equipped swivel hook to the eyebolt.



21.



Securely attach a dial indicator to the housing and locate the stem so the tip is contacting the end of the shaft and movement of the tip is exactly vertical, the same direction as the movement of the shaft.



22.



Lift the unit off the supports using the hoist. Apply approximately 90.7 Kg. (200 lbs.) of downward force on the bearing carrier while dial indicator is being set. Mark a spot on the end of the shaft next to the stem as a starting reference point and set the dial indicator to zero.



Power Take-off Service Manual #1022764



Assembly



Twin Disc, Incorporated



23.



Carefully and gently lower the unit back onto the supports. Allow the hoist to go slack. Apply approximately 90.7 Kg. (200 lbs.) of downward force on the shaft while dial indicator reading is being taken. (The weight of the shaft will be considered part of the 90.7 Kg. (200 lbs.)) Read the dial indicator to read actual bearing end play.



24.



Repeat steps 22 and 23 to be sure the dial indicator reading repeats with accuracy. Remove the capscrews (35), lock plates (36), bearing retainer (38) and shims (37), if necessary, to add or subtract shims to obtain the specified bearing end play. When the correct bearing end play has been set and verified, reinstall the components. Torque the capscrews to the proper specifications given in Torque Values for Fasteners in the Description and Specifications section.



25.



Bend the tabs of the lock plates (36) so they are against the flats of the hex head capscrews. Note: Bump the output end of the shaft with a soft mallet hard enough to move and seat the front bearing cup up against the bearing retainer and create the specified bearing clearance after each adjustment of the bearing retainer.



Install the oil slinger 26.



Invert the shaft unit and support it with the output end resting securely on a solid surface so the press force is carried through the shaft, not against the roller bearings, when the oil slinger (58) and front wear sleeve (63) are installed.



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27.



Carefully mark the shaft at a point that is 20.32 mm. (0.800 inches) below the shoulder. Press the oil slinger (58) on the shaft so the upper lip of the slinger is at the specified position. The flat side will be down toward the bearing retainer. The lip extension at the I.D. will be up, toward the shoulder, located exactly at the marked location. Shoulder



Oil Slinger (58) Bearing Retainer (38)



20.32 mm.(0.800 inches) Clutch Shaft (33)



Figure 44. Mark position of Oil Slinger 28.



Coat the I.D. of the front wear sleeve (63) with an anaerobic sealant Twin Disc part number M2828. Press the sleeve onto the shaft. The flat end of the sleeve should be tight against the oil slinger. When positioned properly, the contoured side will align exactly with the shoulder of the shaft. Be sure the contour blends in with the shoulder of the clutch shaft. Remove excess sealant when sleeve is in its proper position on the shaft.



Wear Sleeve (63)



Oil Slinger (58)



Clutch Shaft (33)



Figure 45. Proper position of Wear Sleeve and Oil Slinger



118



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Twin Disc, Incorporated



Contour is flush. Wear sleeve



Shaft wear sleeve shoulder



Shaft shoulder



Figure 46. Locating the oil seal wear sleeve on the shaft



Check to be sure the oil slinger is not in contact with the clutch housing. 29.



Lift the bearing carrier and shaft using a hoist securely attached to it. Carefully place the bearing carrier and shaft onto the clutch housing (34). Disconnect the hoist. Note: Do not install the rubber seal (50) at this time.



30.



Align the bearing carrier (47) so the fill fitting (72) will be at the top when the pto is installed on the engine, aligned with the instruction cover plate hole.



31.



Install two hex head bolts (48), located 180o apart, and tighten the bearing carrier to the clutch housing.



32.



Slowly rotate the shaft. Carefully listen and feel for contact between the oil slinger and the clutch housing. The oil slinger MUST NOT contact the housing. If it does, remove the bearing carrier and shaft and repeat step 27 by moving the oil slinger a little closer to the bearing retainer. Then repeat this step as necessary to insure no contact exists.



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Install the shaft and bearing carrier in the main housing. 33.



Again remove the bearing carrier. Place the rubber seal (50) on the pilot of the bearing carrier.



34.



Lift the bearing carrier and shaft using a hoist securely attached to it. Carefully place the bearing carrier and shaft onto the clutch housing (44). Disconnect the hoist.



Use extreme care to prevent damage to the oil seal as the shaft passes through it. If the seal lip is damaged, replace the seal before proceeding (see step 6).



Complete the assembly of the bearing carrier and shaft unit. 35.



Install the drain plug (71) and fill fitting (72) in the bearing carrier.



36.



If removed, install the oil gauge tube (67) into the bearing carrier if it was removed. The tube must fit tight enough in the hole so as to require over 133 N. (30 lbs.) to remove it. The tube must seal in the hole so an oil leak does not occur.



37.



Place the support plate in position (if used), and secure the bearing carrier and support plate to the clutch housing with eight hex-head capscrews (48). Torque the capscrews to the proper specifications given in Torque Values for Fasteners in the Description and Specifications section.



38.



Install two flush pipe plugs (52) at the rear of the carrier. Torque the capscrews to the proper specifications given in Torque Values for Fasteners in the Description and Specifications section. Note: Bump the output end of the shaft with a soft mallet (as described in the previous step above) hard enough to move and seat the front bearing cup up against the bearing retainer and create the specified bearing clearance after each adjustment of the bearing retainer.



(Proceed to Install the Operating Shaft and Throwout Yoke)



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Twin Disc, Incorporated



Clutch Shaft and Housing Assembly - Configuration B Refer to the Twin Disc Power Take-Off Reference Listing in the Description and Specifications section, the exploded views in the Illustration section and Engineering Drawings near the back of this manual.



Figure 47. Illustration - Configuration B



Clutch shaft 1.



Clean the main bearing (40) and clutch shaft (33) with isopropyl solvent to remove any oil or grease residue. Note: Do not use any oil or paraffin based solvents.



2.



Use an arbor press to install the bearing (40) on the clutch shaft (33). Install the bearing on the clutch shaft, pressing it tight against the shoulder. Use a piece of steel tubing approximately 5 cm. (2 in.) longer than the distance from the end of the shaft to the shoulder and just slightly larger in inside diameter than the bearing ’s inside diameter. (see note below regarding special tools.)



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Note: Special tools are not available from Twin Disc, Inc., but can be fabricated in any capable machine shop. Note: An alternative method to install the bearing is to heat it in an oven at 135° C. (275° F.) for one hour and install it immediately on the clutch shaft. Let the bearing cool to room temperature after installation while continuing to apply force as the bearing cools. This is necessary to ensure that it remains properly seated.



Press Ram



Note: I.D. of Press Tube is slightly larger than the I.D. of the bearing.



Flat Plate (tool) Press Tube



Note: Thickness of Press Tube wall must contact ONLY the inner race of the bearing.



Bearing (40)



Clutch Shaft (33)



Note: Bearing must be pressed tight against the shoulder.



Figure 48. Install front bearing on the shaft 4.



122



Install the snap ring (59) in the shaft groove.



Power Take-off Service Manual #1022764



Assembly



Twin Disc, Incorporated



Install the clutch shaft and bearings into the bearing carrier. 5.



Place the bearing carrier (47) in a large bench vise with protective jaws or securely support it on a bench with the input end up. There must be sufficient clearance below the carrier to install the shaft. Note: Pre-grease the bearing prior to assembly.



6.



Carefully install shaft and bearing in the bearing carrier. The output end of the shaft must enter the carrier first.



7.



Install the internal snap ring (75) in the bearing carrier.



Install the bearing carrier unit on the clutch housing. 8.



Set the clutch housing (44) on a work bench, securely supported with wooden blocks, with the input end of the housing facing down. There should be sufficient clearance below the housing to allow for installation of the clutch shaft.



9.



Install two grease fittings (57) if they were removed.



10.



Lift the bearing carrier and shaft using a hoist securely attached to it. Carefully lower the bearing carrier and shaft onto the clutch housing. Disconnect the hoist. Position the carrier so the grease fitting (51) will be up when the clutch housing is in its final position on the engine.



11.



Attach the support plate if used, and secure the bearing carrier to the clutch housing with six hex-head capscrews (48) and washers (49). Torque the capscrews to the proper specifications given in Torque Values for Fasteners in the Description and Specifications section.



12.



Install the plug (71) in the grease-purge hole at the bottom of the bearing carrier.



(Proceed to Install the Operating Shaft and Throwout Yoke)



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Twin Disc, Incorporated



Clutch Shaft and Housing Assembly - Configuration C Refer to the Twin Disc Power Take-Off Reference Listing in the Description and Specifications section, the exploded views in the Illustration section and Engineering Drawings near the back of this manual.



Figure 49. Illustration - Configuration C



Clutch Shaft 1.



Clean the front and rear tapered bearings (40 & 41) and clutch shaft (33) with isopropyl solvent to remove any oil or grease residue. Note: Do not use any oil or paraffin based solvents.



2.



124



Use an arbor press to install the two bearings on the clutch shaft. Install the bearings, one from each end, butting against the shoulder on the clutch shaft. Use a piece of steel tubing approximately 5 cm. (2 inches) longer than the distance from the end of the shaft to the shoulder and just slightly larger in inside diameter than the bearing’s inside diameter. The tubing must not be thick enough to contact the cage of the bearing during installation.



Power Take-off Service Manual #1022764



Assembly



Twin Disc, Incorporated



Note: An alternative method to install the bearings is to heat them in an oven at 135° C. (275° F.) for one hour and install them immediately on the clutch shaft. Let the bearings cool to room temperature after installation. Continue to apply force as the bearing cools to room temperature ensuring that it remains seated. Note: I.D. of Press Tube is slightly larger than the I.D. of the bearing.



Press Ram Flat Plate (tool) Press Tube



Note: Thickness of Press Tube wall must contact ONLY the inner race of the bearing.



Bearing (41)



Note: Bearing must be pressed tight against the shoulder.



Output end of Clutch Shaft (33)



Figure 50. Install rear main bearing (41) on the shaft



Bearing Carrier 3.



Set the bearing carrier (47) on the bed of a press with the output end of the housing facing up.



4.



Coat the bearings with a light film of clean No. 30 engine oil.



5.



Hand pack the bearings with grease as described in the Description and Specifications section.



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Install the clutch shaft and bearings into the bearing carrier. 6.



Place the bearing carrier (47) in a large bench vise with protective jaws or securely support it on a bench with the input end up. There must be sufficient clearance below the carrier to install the shaft.



7.



Install the shaft with the bearings in the bearing carrier. The lower bearing must seat securely in the bottom of the bore.



8.



Install bearing retainer (38) in the bearing carrier (47) resting securely against the front bearing (40).



9.



Install six hex head capscrews (35) with washers (36). Torque the capscrews to the proper specifications given in Torque Values for Fasteners in the Description and Specifications section.



Install the bearing carrier unit on the clutch housing. 10.



Set the clutch housing (44) on a work bench, securely supported with wooden blocks, with the input end of the housing facing down. There should be sufficient clearance below the housing to allow for installation of the clutch shaft.



11.



Lift the bearing carrier and shaft using a hoist securely attached to it. Carefully lower the bearing carrier and shaft onto the clutch housing. Disconnect the hoist. Position the carrier so the fitting (51) will be up when the clutch housing is in its final position on the engine.



12.



Attach the support plate if used, and secure the bearing carrier to the clutch housing with six hex-head capscrews (48) and washers (49). Torque the capscrews to the proper specifications given in Torque Values for Fasteners in the Description and Specifications section.



13.



Install 2 lubrication fittings (57) if they were removed.



(Proceed to Install the Operating Shaft and Throwout Yoke)



126



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Twin Disc, Incorporated



Clutch Shaft and Housing Assembly - Configuration D Refer to the Twin Disc Power Take-Off Reference Listing in the Description and Specifications section, the exploded views in the Illustration section and Engineering Drawings near the back of this manual.



Figure 51. Illustration - Configuration D



Clutch Shaft 1.



Clean the front and rear bearing inner races (40 & 41) and clutch shaft (33) with isopropyl solvent to remove any oil or grease residue. Note: Do not use any oil or paraffin based solvents.



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2.



Use an arbor press to install the front bearing inner race (40) on the clutch shaft. Install the race, butting tight against the shoulder on the clutch shaft. Use a piece of steel tubing approximately 5 cm. (2 inches) longer than the distance from the end of the shaft to the shoulder and just slightly larger in inside diameter than the race’s inside diameter. Note: Special tools are not available from Twin Disc, Inc., but can be fabricated in any capable machine shop. Note: An alternative method to install the bearing race is to heat it in an oven at 135° C. (275° F.) for one hour and install it immediately on the clutch shaft. Let the race cool to room temperature after installation. Continue to apply force as they cool ensuring that they remain seated.



Note: I.D. of Press Tube is slightly larger than the I.D. of the Bearing Race.



Press Ram Flat Plate (tool) Press Tube



Front Bearing Inner Race (40) Clutch Shaft (33)



Note: Race must be pressed tight against the shoulder.



Figure 52. Install the front bearing inner race on the shaft 128



Power Take-off Service Manual #1022764



Assembly



Twin Disc, Incorporated



3.



Use an arbor press to install the inner race of rear bearing (41) on the clutch shaft. Install the race, butting tight against the shoulder on the clutch shaft. Use a piece of steel tubing approximately 5 cm. (2 inches) longer than the distance from the end of the shaft to the shoulder and just slightly larger in inside diameter than the race’s inside diameter. Note: Special tools are not available from Twin Disc, Inc., but can be fabricated in any capable machine shop. Note: An alternative method to install the bearing race is to heat it in an oven at 135° C. (275° F.) for one hour and install it immediately on the clutch shaft. Let the race cool to room temperature after installation. Continue to apply force as they cool ensuring that it remains seated.



Note: I.D. of Press Tube is slightly larger than the I.D. of the bearing.



Press Ram Flat Plate (tool) Press Tube



Note: Bearing must be pressed tight against the shoulder.



Bearing Inner Race (41)



Output end of Clutch Shaft (33)



Figure 53. Install the rear bearing inner race on the shaft



Install the clutch shaft and bearings into the main housing. 4.



Support the housing (44) with the output end up. There must be sufficient clearance below the housing to install the shaft.



5.



Hand pack the bearings with grease as described in the Description and Specifications section.



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6.



Apply grease to the circumferential cavities in the housing (44) and bearing retainer (38) as a seal against water and contaminants, and to the inside surfaces of the housing and bearing retainer that contact the bearing.



Bearing Retainer (38) Grease Locations Housing (44)



Figure 54. Apply grease before assembly 7.



Carefully install the outer race of the front bearing (40) in the housing bore.



8.



Carefully install shaft in the housing.



Use extra care to prevent damage to the bearing rollers or races during shaft installation. Damage will cause premature failure.



130



9.



Install the bearing retainer (38) on the housing and secure with six hex head capscrews (35) and six washers (36). Torque the capscrews to 80 Nm (59 lb.-ft.).



10.



Install 2 lubrication fittings (57) if they were removed.



Power Take-off Service Manual #1022764



Assembly



Twin Disc, Incorporated



11.



Determine the position the sheave housing will be in when the pto is installed on the engine. The sheave housing must be piloted on both dowel pins. Install the dowel pins (61) in the appropriate holes in the main housing.



12.



Apply grease to the circumferential cavities in the sheave housing (60) and bearing retainer (64) as a seal against water and contaminants, and to the inside surfaces of the housing and bearing retainer that contact the bearing.



Bearing Retainer (64) Grease Locations Sheave Housing (60)



Figure 55. Apply grease before assembly



13.



Install the sheave housing (60), locating it on the dowel pins. Secure it with the six hex head capscrews (48). Torque the capscrews to the proper specifications given in Torque Values for Fasteners in the Description and Specifications section.



14.



Install the outer race of the rear bearing (41) in the sheave housing. Tap the race to the bottom of the bore.



15.



Hand pack the bearing with grease as described in the Description and Specifications section.



16.



Install the bearing retainer (64) on the sheave housing and secure with three hex head capscrews (65) and three washers (66). Torque the capscrews to the proper specifications given in Torque Values for Fasteners in the Description and Specifications section.



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17.



Install the cover (75) on the bearing retainer (64) and secure with four capscrews (76). Torque the capscrews to the proper specifications given in Torque Values for Fasteners in the Description and Specifications section.



Measure the bearing end play (shaft movement) as shown in Checking Bearing End Play - Model SP318SB Series in the Maintenance section (Proceed to Install the Operating Shaft and Throwout Yoke)



132



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Twin Disc, Incorporated



Install the Operating Shaft and Throwout Yoke. Refer to the Twin Disc Power Take-Off Reference Listing in the Description and Specifications section, the exploded views in the Illustration section and Engineering Drawings near the back of this manual.



1.



Position the clutch housing on a bench with the input end facing up. Install the operating shaft (55) halfway into the clutch housing. Slip the throwout fork (54) onto the operating shaft and push the shaft through to the hole on the other side of the clutch housing far enough to expose one of the woodruff key slots at the center of the throwout fork.



2.



Install one woodruff key (56) in the operating shaft.



Clutch Shaft (33) Note position of throwout fork (54)



Bearing Carrier (47)



Operating Shaft (55)



Figure 56. Install the throwout fork 3.



Push the operating shaft the other way to expose the other key slot in the center of the fork.



4.



Install the other woodruff key (56).



5.



Center the operating fork so the hex head capscrews will enter the bottom of the throwout fork and thread into the top section. Install the two hex-head capscrews and tighten. Torque the capscrews to the proper specifications given in Torque Values for Fasteners in the Description and Specifications section.



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6.



Install the stop collar (76) (if used) per instructions given in Hand Lever Position for Twin Disc Power Take-Offs in the Installation section of this manual. Note: Some units, such as in the SP318SB Series, use a stop collar even though the pto is not normally installed with the operating shaft in the vertical position.



(Proceed to PTO Final Assembly)



134



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Twin Disc, Incorporated



PTO Final Assembly Install the clutch in the clutch housing. Refer to the Twin Disc Power Take-Off Reference Listing in the Description and Specifications section, the exploded views in the Illustration section and Engineering Drawings near the back of this manual. 1.



Set up and support the main housing assembly (44) with attached parts on the bench with the input side facing up. Note: The output end of the shaft must rest securely on a solid surface.



2.



3.



Carefully place the clutch assembly over the clutch shaft while: A.



Aligning the trunnions on the collar with the throwout fork.



B.



Aligning the keyways in the hub-and-back plate with the keyway in the clutch shaft.



Partially install the hub key (29) in the keyway. Tap the hub-and-back plate with a large, but soft mallet, to seat it on the tapered surface of the clutch shaft.



Be sure the output end of the shaft is resting on a solid surface to absorb the force through the shaft rather than through the bearing surfaces. Clutch Key (29)



Clutch Rotate throwout fork to engage trunnion. Use several 4” x 4” blocks or other means of insuring the pto does not tip or fall over.



1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234 1234



123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123 123



Clutch Shaft (33)



Output end of the shaft MUST rest and be in contact with a solid support (Press bed).



Figure 57. Assemble clutch into Power Take-Off Power Take-off Service Manual #1022764



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Assembly



Twin Disc, Incorporated



4.



Drive the hub key (29) into position slightly below the surface of the huband-back plate (4). Note: Do not use excessive hammer force when installing the key.



5.



Install the hub nut lock washer (3) over the clutch shaft (33), locating its tab in the drilled hole on the hub-and-back plate (4). Install the hub nut (2) and tighten and torque to 40.7 Nm. (30 ft. -lb).



6.



Tighten the hub nut an additional amount clockwise, as shown in the chart belowm then bend a side of the hub nut lock washer up against a flat on the hub nut. Table 19. Hub Nut Advance After Initial Tightening



Model Number



Rotate Hub Nut Clockwise the Additional Amount Shown



SP218OP Series



180 - 210 degrees



SP318P Series



240 - 270 degrees



SP318IL Series



150 - 180 degrees



SP318SB Series



150 - 180 degrees



SP321P Series



210 - 240 degrees



7.



Route the flexible hose assembly (19) clear of all moving parts and push the end hose fitting (20) through the hole in the clutch housing.



8.



Install the lock washer (21) and jam nut (22) to retain the end fitting (23) in the housing. Torque the capscrews to the proper specifications given in Torque Values for Fasteners in the Description and Specifications section.



Confirm that the hose assembly is not twisted or applying preload to the collar assembly. 9.



136



Install all remaining plugs and external components on the power takeoff.



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Twin Disc, Incorporated



Center the clutch plates 10.



If not previously done, visually center the friction plates (6) on the clutch and align the teeth. Press down on the collar assembly to lock the plates in place. If necessary, pull the adjustment lock pin to compress the lock pin spring, and rotate the adjusting yoke assembly until the plates are locked in position when the collar is pressed down. Note: This is an initial setting to hold the plates in place until after the pto is mounted on the engine, so it is imperative that the teeth be exactly aligned and the plates are exactly centered on the clutch. The driving ring may be used as an alignment fixture to align the teeth and center the plates relative to the hub-and-backplate so they are perfectly aligned when the pto is installed on the engine. Perfectly center the clutch in the drive ring. (This gap is to be exactly equal all the way around.) Visually align Driving Ring relative to housing bore.



Figure 58. Using the driving ring as an alignment tool



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Final assembly and lubrication.



138



11.



Install the power take-off according to instructions in the Installation section of this manual.



12.



Adjust the clutch according to Clutch Adjustment in the Maintenance section of this manual.



13.



Fill the main bearing cavity with grease or oil according to lubrication specifications in the Maintenance section and Filling the Main Bearing Cavity during initial assembly in the Description and Specifications section of this manual.



14.



Lubricate the remainder of the pto according to lubrication specifications in the Description and Specifications section of this manual.



15.



Place the instruction cover plate (43) in position on the housing and secure with 2 hex-head cap screws 5/16” - 18 x 1/2” (42). Torque the capscrews to the proper specifications given in Torque Values for Fasteners in the Description and Specifications section.



16.



Place the bottom cover plate (62), if used, in position on the housing and secure with 2 hex-head cap screws 5/16” - 18 x 1/2” (74). Torque the capscrews to the proper specifications given in Torque Values for Fasteners in the Description and Specifications section.



17.



Install the shaft key (34) and all parts previously removed from the output end of the clutch shaft.



Power Take-off Service Manual #1022764



Illustrations



Twin Disc, Incorporated



Illustrations



List of Illustrations The following pages include illustrations that are specific to this model. The illustrations included are listed below. Note: Any part numbers listed in the following illustrations are for reference only. Please refer to your bill of material for part numbers specific to your model.








Parts Identification List - SP218, SP318, SP318SB, and SP321 Series








Exploded View (SP218 and SP318 Series Clutches)








Exploded View (SP321 Series Clutches)








Exploded View (Configuration A)








Exploded View (Configuration B)








Exploded View (Configuration C)








Exploded View (Configuration D)



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Illustrations



Twin Disc, Incorporated



Parts Identification List - SP218, SP318, SP318SB, and SP321 Series



Item 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38



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Description



Qty.



Pilot Bearing 1 Nut 1 Washer 1 Hub-and-Back Plate 1 Ring, Drive 1 Plate, Friction 1,2 or 3 Plate, Center 1 or 2 Plate, Pressure 1 Lever 4 Washer (lever to pressure plate) 4 Pin, Clevis (lever to pressure plate) 4 Pin, Cotter (lever to pressure plate) 4 Pin, Cotter (lever to link) 4 Pin, Clevis (lever to link) 4 Link 4 Pin, Clevis (link to sleeve) 4 Pin, Clevis (link to sleeve) 4 Fitting 1 Hose 1 Fitting 1 Washer 1 Nut 1 Fitting, Grease 1 Spring, Compression 1 Pin 1 Yoke, Adjusting 1 Sleeve, Sliding 1 Collar Assembly (collar) 1 Ring, Snap-external 1 Bearing, Ball 1 Ring, Snap-internal 1 Key-Clutch 1 Shaft, Clutch 1 Key-output 1 Capscrew, Hex-head 6 or 12 Washer 6 or 12 Shims AR Retainer, Bearing 1



Item Description Qty. 39 Bearing, Cup-front 2 40 Bearing, Cone-front (or bearing-qty. 1)2 41 Bearing, Cone-rear (or bearing-qty. 1) 2 42 Bearing, Cup-rear 2 43 Oil Deflector 1 44 Housing 1 45 Plate, Instruction 1 46 Screw, machine 2 47 Carrier, Bearing 1 48 Screw, hex-head 6 49 Washer 6 50 Fitting 1 51 Fitting 1 52 Plug 2 53 Hand Lever Assembly 1 54 Throwout yoke 1 55 Shaft, Operating 1 56 Key, woodruff 2 57 Fitting (or plug) 2 58 O-Ring Seal 1 59 Snap Ring, external 1 60 Sheave Housing 1 61 Dowel Pin 2 62 Plate, Bottom 1 63 Sleeve, Wear-front 1 64 Seal Plate (or rear bearing retainer) 1 65 Capscrew 3 66 Oil Gauge 1 67 Oil Gauge Tube 1 68 Seal, Oil-front 1 69 Sleeve, Wear-rear 1 70 Seal, Oil-rear 1 71 Plug, pipe 1 72 Fitting, Fill 1 73 Grease Shield 1 74 Capscrew 2 75 Cover 1 76 Capscrew 4



Power Take-off Service Manual #1022764



Illustrations



Twin Disc, Incorporated



Exploded View (SP218 and SP318 Series Clutches) Note: Typical unit illustrated.



Typical SP218 Series Clutch (Bronze Throwout Collar shown)



Typical SP318 Series Clutch (Ball-Type Throwout Collar shown) Power Take-off Service Manual #1022764



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Illustrations



Twin Disc, Incorporated



Exploded View (SP321 Series Clutch) Note: Typical unit illustrated.



Typical SP321 Series Clutch (Bronze Throwout Collar shown)



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Power Take-off Service Manual #1022764



Twin Disc, Incorporated



Illustrations



Exploded View (Configuration A) Note: Typical unit illustrated



.



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Illustrations



Twin Disc, Incorporated



Exploded View (Configuration B) Note: Typical unit illustrated



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Twin Disc, Incorporated



Illustrations



Exploded View (Configuration C) Note: Typical unit illustrated



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Illustrations



Twin Disc, Incorporated



Exploded View (Configuration D) Note: Typical unit illustrated



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Engineering Drawings



Twin Disc, Incorporated



Engineering Drawings The engineering drawings included are listed below. Note: All part numbers listed in the following engineering drawings are for reference only and illustrate most of the variations found in the SP111, SP211 and SP311 Series PTOs. Please refer to your bill of material for part numbers specific to your model. Contact your Authorized Twin Disc Dealer for the latest BOM and engineering drawings.




SP218P



SP218P001 Sheet 2 of 2 (Configuration A)








SP318P



SP318P001 Sheet 2 of 2 (Configuration B)








SP318IL



SP318P011 Sheet 2 of 2 (Configuration C)








SP318SB



SP318S001 Sheet 2 of 2 (Configuration D)








SP321P



SP321P901 Sheet 2 of 2 (Configuration B)








SP218 Clutch



SP218C001 Sheet 2 of 2








SP318 Clutch



SP318C001 Sheet 2 of 2








SP318 Clutch



SP318C003 Sheet 2 of 2








SP321 Clutch



SP321C001 Sheet 2 of 2



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Introduction



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Twin Disc, Incorporated



TWIN DISC, INCORPORATED RACINE, WISCONSIN 262-638-4000/262-638-4482 WWW.TWINDISC.COM EC300 Marine Control System53403, ConfiU.S.A. guration/Troubleshooting Manual (FAX) #1020XXX