Document 1ypnDYbaqk3wY6MZGboEEqb9q

DIRECT OML (407) 244-1165 DIRECT FACSIMILE (407) 648-4864 INTERNET E-MAIL CKOLOSQMVW.COM Maguire, Voorhis & Wells, P.A. at JQcuv TWO SOUTH ORANGE PLAZA 2 SOUTH ORANGE AVENUE ORLANDO, FLORIDA 32801 TELEPHONE (407) 244-1100 FACSIMILE (407) 423-8796 P.O. BOX 633 ORLANOO, FLORIDA 32802 June 25, 1997 PLAINTIFF'S EXHIBIT N.Chris Kolos David M. Lipman, Esquire 5901 S.W. 74th Street Suite 304 Miami, Florida 33143 Re: Tinker v. Mack Trucks, Inc., et a/. Ontario County index No.: 83778 Dear Mr. Lipman: Enclosed please find additional documentation produced by Mack Trucks, Inc. in response to paragraphs seven and eleven of Plaintiff's Request for Production. As before, its investigation and search are ongoing and as documents are produced to me that are responsive to the requests, I will be producing them to you. If you have any questions, please do not hesitate to contact me. CNK:jo Enclosures ORLANDO MELBOURNE TALLAHASSEE Disc Brakes No manual adjustment required. Brakes adjust automatically during braking oper ation. The square-cut piston seal is dis torted when pressure is applied to piston. When braking pressure is released, the seal returns to its normal condition and pulls the piston away from the lining. This action, plus some slight rotor lateral runout ("wob ble"), considerednormal, provides adequate running clearance. Disassembly and Assembly When brakes are relined or disassembled for other repairs, all parts should be in spected for wear and worn parts should be replaced as required. Cam Brakes - (See Figure 8-37) Disassembly 1. Remove shoe return spring. 2. Remove lock rings, retainers, and felts from brake shoe anchor pins. 3. Cut lock wire and remove anchor pin lock screws. 4. Remove anchor pins and shoe assemblies. 5. Remove brake shoe roller retaining clip (or screw) and remove roller. 6. Remove slack adjuster lock ring and spacing washers. 7. Remove camshaft, washer, and felt seal (if used ). 8. Remove nylon bushings if replacement is necessary. Use suitable tool for both re moval and installation of bushing. See Figure 8-44. NOTE On brakes where lip type seals are used, these will have to be removed and replaced if nylon bushings are replaced. Figure 8-44. Bushing Removal and Installation Tool 8-42 Assembly 1. Install new nylon bushings, if required, using suitable tool. (Install new lip type seal if used.) 2. Install brake shoe rollers and retainers. Make certain rollers are of proper size. See instructions relative to brake shoe "Cam Roll-Over." 3. Install camshaft, washer, and felt seals, (if used.) 4. Position brake shoe assembly over spi der and tap anchor pin into position with brass punch, "flat" in line with lock screw hole. 5. Install lock screws, tighten securely and thread with lockwire. 6. Position felts, retainers, and lock rings on anchor pins. 7. Install shoe return spring. New springs should be used with each brake reline. Ten sion loss occurs from normal use and heat build up. New springs will ensure that shoes are returned to fully relaxed position, and not in contact with drum, which would cause premature wear. 8. Assemble slack adjuster on splined end of camshaft; using spacers and washers on each side of adjuster to obtain. 030-. 060 end play. Wedge Brakes - (See Figure 8-39) Disassembly 1. Remove shoe return springs. Use brake spring pliers. (Do Not use screwdriver.) 2. Remove brake shoe assembly. 3. Remove plunger guide screws and gaskets from plunger housing. If brake is automatic adjusting, remove hollow capscrew, gaskets, spring and adjusting pawl. It may be neces sary to use a magnet to remove the adjusting pawl. 4. Using a suitable screwdriver, pry the seals loose and remove anchor (solid) plungers, adjusting plungers, adjusting sleeves (actuators) and adjusting bolts. 5. Thoroughly inspect and clean all parts including the housing plunger and seal bores and shoe rest pads. DO NOT solvent clean any rubber parts (plunger seals or gaskets). 3k Wire brush plunger parts and adjusting bolt threads to remove caked on dirt and cor rosion. 4. Make sure anchor plungers marked "L" are installed in left hand brake and anchor plungers marked "R" are installed in the right hand brake. Carefully inspect plunger seals and gaskets for tears, cuts or deterioration, and replace if necessary. Also check the angled plunger roller faces for pits, grooves or nicks and replace if necessary. NOTE 5. Coat entire anchor plunger with grease, packing cavity behind seal, and insert plunger and seal into housing with plunger keyway slot aligned with guide screw hole. Make certain the plunger goes all the way into the plunger bore and seats on bosses at the bottom. Brakes have one adjusting plunger and one anchor (solid) plunger per plunger housing. The anchor plungers are marked on the shoe slot end, "R" for right hand brakes and "L" for left hand brakes. DO NOT mix at reas 6. Seat plunger seal in plunger housing with correct seal driver tool. Driver must be centered over seal retainer to prevent dam age to seal assembly. NOTE i sembly. Assembly - Anchor (Solid) Plunger CAUTION Do not inter-mixwedge and plung er assembly components. Wedge and plunger assemblies are fur nished with either a 12 degree or 14 degree contact surface angle. Plungers are additionally supplied as "Right" or "Left" for install ation in corresponding right or left hand brakes. Any inter mixing of these parts will cause W- erratic and uneven braking. If seal driver is not available, a 1-3/4" wrench socket can be used for spider mounted brakes and 1-3/8" wrench socket can be used for backing plate mounted brakes. 7. Assemble gasket and guide screw into plunger housing. Make certain guide screw end enters the plunger key-way slot so plunger can slide freely in housing bore. Tighten guide screws to 15 to 20 lb. ft. torque. Assembly (Manual Adjusting Plungers) 1. Apply film of grease to inside surfaces of seals. 1. To assemble seals into plungers, apply a film of grease to inside surfaces of seals. See Figure 8-40. 2. Inspect nose for burrs. Mask brake shoe web slot in the plunger nose with mask ing tape to protect seal. 2. Push the inner seal lip over the threaded hole end of the plunger until the lip com pletely enters the plunger seal groove. 3. Apply grease to outside of plunger and in stall plunger and seal into plunger housing in the same manner. Refer to AssemblyAnchor (solid) Plunger steps 5, 6 and 7. Carefully push the double lip seal onto the plunger, stretching the outer seal lip over 4. Coat adjusting bolt threads with grease *+ V the plunger nose end, until the inner seal lip and turn bolt into the adjusting plunger by is completely in the second plunger groove working it through the hole in the outer seal :3P. and the outer seal lip is in the first plunger flap, being careful not to pinch the seal on groove. Remove masking tape. (Brakes the threads. Turn adjusting bolt in just short employing single grooved plungers and single of the seal. DO NOT bottom bolt on the seal. *V lip seals should be assembled in the same manner except masking tape is not used.) Assembly (Automatic Adjusting Plungers) IMPORTANT: DO NOT ASSEMBLE SEALS INTO PLUNGER HOUSING FIRST. THIS WILL RESULT IN COMPLETE LACK OF SEALING OF INTERNAL PLUNGER HOUSING COMPONENTS. 3. Coat all plunger bores with grease. Two types of automatic adjusting plungers are being used. The latest designed parts are readily identified since the new plunger seal has only a single sealing lip instead of a double lip. The adjusting bolt of the latest design also has a retaining ring. 8-43 & 4 Sr r Figure 8-50. Removing Caliper NOTE It is not necessary to remove the hydraulic line when replacing shoe and lining assemblies. How ever, do not let the caliper hang on the hydraulic line. Lay the caliper on the suspension. Inspecting Caliper 1. Check the inside of caliper for hydraulic fluid leak. If evidence of fluid leak is noted, the caliper should be overhauled. 2. Wipe the inside of the caliper, clean and check the dust boots for cuts, cracks or other damage. If damage is noted the caliper should be overhauled. See Figure 8-53. Removing Shoe and Lining Assembly 1. Remove the inner shoe and lining assem bly from the anchor plate. 2. Remove outer shoe and lining hold-down spring, pin and cup. See Figure 8-51. Figure 8-53. Inspecting Boots for Cracks and Cuts. Figure 8-51. Removing Spring, Pin, and Cup. 3. Remove outer shoe and lining assembly. See Figure 8-52. Assembly Installing Shoe and Lining Assemblies 1. Install new inner shoe and lining as sembly into anchor plate. 2. Push the pistons to the bottom of the pis ton bore. This is done by taking a small block of wood and placing it over the pistons and boots. With a "C" clamp, push the pistons to the bottom of the piston bores. 3. This will provide clearance for the caliper to fit over the hub and rotor when new shoe and linings are installed. See Figure 8-54. J s* leading to the bottom of the container. The air then rises through the alcohol and passes into the line to the compressor, carrying alcohol in the form of vapor with it. The alcohol, thus introduced into the air system acts as an anti-freeze. Figure 8-82. Alcohol Evaporator Preventive Maintenance Every 1, 000 Miles or as Determined by Act ual Usage Check alcohol level and if necessary replenish with 188 proof methanol alcohol. In cold weather, alcohol level should be at least 2/3 full. NOTE If alcohol is not being consumed, it indicates the evaporator is in operative and shouldbe inspected. Every Mack C Inspection Remove strainer if present in bottom of evap orator body and clean thoroughly in solvent. Every Mack C Inspection Disassembly evaporator unit and clean thoroughly. Inspect all parts for cracks and be sure evaporator tube is not clogged with dirt. Replace all gaskets and rubber parts. Inspection When the compressor is compressing air, air bubbles should be passing through the alcohol. If air bubbles are not present when the compressor is compressing air, then the alcohol evaporator is not functioning properly. Check to be sure all connections are tight. Check condition of filler cap gasket and cover gasket. RE LINING & RECONDITIONING Drum-Type Brakes After supporting the axle on stands, cage the springs in the spring brake chambers. Re move the tires, wheels, and drums as an assembly, and inspection drums for heat checks, cracks, distortion or other damage. Close inspection of all worn brake parts may lead to clues for corrective action to improve lining life and future drum damage. Scored Drum Only the tops of the ridges will contact brake lining. Since a small percentage of the brake lining is required to do all the work, hard pedal and fade will result. A scored drum must be reconditioned in a lathe. See Figure 8-83. Hard spots are "islands" of steel in the cast iron surface. They result from a change in metallurgy caused by the heat of braking Hard spots must be ground out or brake perform ance will be poor and erratic. See Figure 8-84. Bell-Mouthed Drum If a drum is bell-mouthed or flared, full lining to drum contact cannot be achieved. Fade and noise can be expected. A bell-mouthed drum must be trued in a lathe in order to pro cure full lining to drum contact. See Figure 8-85. 8-63 CLUTCH REMOVAL 1. Mark clutch cover and flywheel with a center-punch before removing clutch to facilitate reinstalling clutch in same posi tion. 2. Use three spring retention tools (J26450 for CL-28, 40 and 50 series, J26451 for CL-47 series) or retaining cups as shown in Figure 4-1, when removing a clutch as sembly from the flywheel. Figure 4-1, Retaining Cups To use spring retention tools, bottom screws in tapped holes in pressure plate. Set tool nuts up snugly against tool bracket. Tighten tool nuts evenly to relieve spring tension on pressure plate. Not used on CL-58 Series. 3. Remove two clutch-to-flywheel cap screws with lockwashers at the ten o'clock and two o'clock positions of the flywheel and install two long headless guide studs to support the clutch assembly during re moval of the remaining attaching capscrews. 4. After removal of all capscrew fasten ers, carefully remove heavy clutch and disc assembly from flywheel counterbore and place on bench. Be careful not to drop driven disc assembly which is now free. Also remove the temporary guide studs from flywheel. CLUTCH INSTALLATION 1. Using spring retention tools, bottom screws in tapped holes in pressure plate. Set tool nuts up snugly against tool brack et. Not used on CL-58 Series. NOTE Three retaining cups and screws are used to hold a new clutch as sembly together until it is in stalled on the flywheel. Spring cups are pressed into the clutch cover hence the retaining cups are necessary to prevent spring cups loosening and slipping out of the cover during handling. Re taining cups and screws must be removed after the clutch is as sembled to the flywheel. A tag is attached to new clutches (CL-28, 40 and 50 Series) calling attention to this fact and cups and screws are painted red for ready identi fication. 2. Engage splined end of clutch disc align ing mandrel or a spare main driving pinion with hub splines of driven disc from rear of long hub side. Then position driven disc assembly in flywheel so that spigot end of shaft engages inner race of clutch pilot bearing mounted in flywheel. This arrangement positions the disc assembly in proper alignment until clutch is com pletely assembled and secured in flywheel. 3. Install two long guide studs in the ten and two o'clock positions in flywheel rim. Mount clutch assembly on guide studs and push unit into flywheel bore until clutch cover flange enters counterbored pilot pro vided. Be careful not to disturb disc aligning mandrel. 4. Lubricate and install cover-to-flywheel capscrews with their lockwashers. Tighten capscrews a few turns at a time so that cover will not be misaligned andforcedinto flywheel pilot by the tightening of the cap screws. Remove the two guide studs and re place with capscrews and their lock wash ers. Remove aligning mandrel. CL-28 and 40 SERIES Description CL-28, -40 Series assemblies are single plate, dry disc pusher type clutches. They consist of a pressure plate, a cover, and a driven disc which is splined to the trans mission main driving pinion shaft. When 4-3 engaged, the driven disc is clamped between the pressure plate and the flywheel by the pressure of coil springs which are mounted in cups on the cover. Drive is transmitted to the pressure plate by pressure plate lugs which fit in the cover openings. Six re lease levers have ball pivots and are linked to the pressure plate by eyebolts. The in ner ends of the levers are held by the notched release thrust washer. See Figure 4-2. 1. Clutch Spring 12. Washer (outer) 13. Fulcrum Adjust 2. Clutch Spring (in ment Nut ner, where used) 14. Lock Nut 3. Release Bearing 15. Eyebolt 4. Release Collar 16. Eyebolt Pin 5. Thrust Washer 17. Cover Plate 6. Release Lever 18. Pressure Plate 7. Lever Spring 19. Flywheel 8. Spring Washer 20. Pilot Bearing 9. Lever Pivot 21. Driven Disc 10. Lever Bushing Assembly 11. Eyebolt Ful 22. Driven Disc crum Facings Figure 4-2. Sectional View of CL-28, 40 Series Clutch 4-4 Disassembly 1. Before disassembly of the various parts, mark these parts with a center-punch, so that at reassembly, they can be reassembled in their original positions. This is neces sary in order not to disturb the dynamic balance of the clutch. 2. Before removing the three spring re tention tools, compress clutch release lever springs, remove washer pins, then remove washers and release lever springs. Pry off snap ring from thrust washer. Remove eyebolt nuts, fulcrums, and clutch release levers. CAUTION : If retaining cups are used instead of tool (J26450) , clamp the cover in a press before removing the cups. This is necessary be cause the screw used does not have sufficient thread length to com pletely release the spring load before coming out of the pressure plate. 3. While holding spring retention tool screws, back off tool nuts alternately mak ing one turn at a time. When spring is entirely relieved, back out the three tool screws. 4. Remove clutch cover and springs. If heat-insulating washers are removed from pressure plate spring pockets, retain them for reassembly. The eyebolts need not be removed unless inspection reveals distor tion or loose fit on pins. Inspection and Repair 1. Remove all traces of dirt and oil with a suitable safety solvent. Inspect parts care fully for cracks, distortion or excessive wear as described in the following steps. 2. If cover is cracked or distorted, re place. Tack-weld loose spring cups (on covers having this construction) replace worn or loose ball-fulcrums. Replace loose or bent pin rivets. 3. Replace springs if cracked or defective. Check all springs on a spring tester. Re place all springs that do not meet specifica tions. 4. Replace thrust washer if worn, bent or defective. 5. Replace worn release levers, springs and ball seats. Check levers with a straight edge and 11/16 inch ball (J26453), see Figure 4-3, and if bent so that dimension (1) is more than 11/32 inch when measured at a point where distance (2) is 2-1/2 inch, replace the lever. Figure 4-3. Checking Release Lever for Bend 6. If pressure plate is scored, heat check ed, or warped more than 0.020 inch, it must be replaced or refaced. Remove only enough metal to obtain a smooth flat sur face. Finish with a light cut and polish with emery cloth. When thickness (1) be comes less than the worn limit given in specifications, the plate must be replaced. Measure at outer spring pocket, see Fig ure 4-4. Measuring at inner pocket is not accurate, if pressure plate is dished. If cleft lugs are worn, cracked or distorted, replace the plate. Replace eyebolts if they are distorted, have worn threads or keyways. Figure 4-4. Pressure Plate Thickness Dimension 7. If flywheel is warped or heat checked and surface is refinished, maintain the 1.594 inch dimension between disc sur face and bolting face for proper release lever adjustment. See Figure 4-5. No more than 0.070 inch maximum may be removed by grinding. Figure 4-5. Flywheel Rubbing Surface-toClutch Cover Bolting Surface Dimension 8. Inspect driven disc assembly for cracks, loose rivets, worn splines, warped or dished condition. If cracked, or hub splines are worn excessively, replace disc assembly. If facings are worn down nearly even with countersunk facing-retaining rivet heads and provided assembly is in other wise good condition, it may be rebuilt. 9. Pilot bearing should be removed, clean ed and checked each time clutch or engine is removed. Discard bearing if balls or races are chipped or scored. After inspec tion, hand-pack bearing with recommended clutch pilot bearing grease and install bear ing in flywheel. Tap into place with shielded side toward clutch and snap ring seated in counterbore. All current Mack-made engine flywheels have been manufactured by boring the clutch pilot bearing hole straight-through and counterboring a recess to provide proper positioning for the snap ring type pilot bear ings now in use. Old bearings without a snap ring cannot be used in new through - bored flywheels. CAUTION Do not install a new snap ring bearing in an old flywheel without removing the snap ring and dis carding. In old flywheels without the counterbore, the snap ring would position the bearing too far rearward, which would result in early bearing failure and consid erable damage to costly compon ents. Use only the recommended snap ring type bearings specified. These bearings will function with out premature failure where slight misalignment exists between en gine and transmission. After bearing Is properly Installed, pack the cavity in back of the bearing with recom mended clutch pilot grease. 4-5 CAUTION To prevent damage to the bearing seal when the transmission is as sembled to the engine, the space occupied by the main driving pinion pilot must not be filled with grease. See Figure 4-6. FLYWHEEL CLUTCH PILOT BALL BEAR)* (SNAP-RING TYPE) WITH BUILT-IN CREASE SEAL HAND-PACK CAVITY EXACTLY AS SHOWN AFTER BALL BEARING INSTALLATION. CENTRAL AREA MUST BE CLEAR OF CREASE BEARING snap-ring COUNTERBORE I7-MJ Figure 4-6. Cut-away View of Clutch Pilot Bearing Grease Reservoir Correctly Packed Before assembling the clutch, a positive wear check should be made to insure that it will provide maximum disc wear. This check will uncover any wear conditions that might prevent full release lever travel and allow corrections to be made before the clutch is assembled. Place the pressure plate assembly and cov er (without springs) into position as shown in Figure 4-7, making sure that shims of the correct thickness (0.200) are inserted between cover and spacer (J26458). In stall each release lever and while pressing firmly on the fulcrum, measure distance (1) inboard end of lever is above cover. 4-6 Correct height for the CL-28Series, 3-9/32 inches, for the CL-40 Series, 3 inches. Reassembly 1. Remove the shims used for the wear check. Lightly lubricate pivot ball bush ing, fulcrum groove, eyebolt pin and in board end of release lever with clutch lever grease. 2. Place the pressure plate on a face plate with the spring pockets of the pres sure plate up. Shellac the washers in place to facilitate retention; place heat-insulating washers and the springs in the pressure plate spring pockets. NOTE If pressure plate was refaced, in sert washers into the spring cups of a thickness equal to the metal removed from the pressure plate. 3. Place the cover in position, align the springs in the pockets. Bottom the screws of the three spring retention tools into the threaded holes of the pressure plate and bring the tool nuts down snugly against the tool bracket. Tighten the tool nuts alter nately, one turn at a time, guiding the pres sure plate lugs into the clutch cover holes until the inside face of the cover is 1.125 inch from the face of the pressure plate. Special tool (J26458), is used to facilit ate obtaining this dimensions, see Figure 4-8. 4. Place the clutch release levers on the ball fulcrums and eyebolt shanks. Place the lever springs on the spring pins with the small diameter against the release levers. 2. Equally space three steel blocks 3/8 inch thick, on bed of arbor or drill press. 3. Place clutch with pressure plate side down, on blocks. (This is done in order to raise clutch to permit disassembly). 4. Place a block of wood, such as a two by four, across cover plate in a position that does not interfere with tips of release levers, as shown in Figure 4-10. Compress clutch assembly slightly, removing lever adjusting screw locknuts. 2. Check cover plate for distortion, ex cessive wear at indentations which register between drive bosses on pressure plate, and for stripped threads in holes accommodating release lever adjusting screws. If the above mentioned conditions are apparent, replacement of cover plate is required. 3. Replace springs if cracked or defective. Check all springs on a spring tester. Re place all that do not meet specifications. 4. Replace release levers that are badly worn on tips (this is an indication of a stick ing release bearing), worn threads on lever adjusting screws and nuts, or where bind ing appears to be present, which retards free back and forth movement. NOTE Release levers are serviced as a subassembly only, and consist of lever, adjusting screw, roller, rol ler block, lever spring and spring retaining pin. Figure 4-10. Compressing Clutch 5. Turn each lever adjusting screw down (clockwise), a few turns with a screw driver, releasing spring tension a small amount. Repeat operation until all lever adjusting screws are entirely free of cover plate. Release remaining spring tension, and lift cover plate off pressure springs. 6. Pressure springs may nowbe removed. After extracting cotter pins and lever pins, remove release levers. Inspection and Repair 1. Clean all parts thoroughly with a suita ble safety solvent. Inspect carefully for excessive wear, distortion, or cracks as described in the following steps. 4-8 5. If pressure plate shows signs of scor ing, excessive wear at lever pin holes, inside of drive bosses, heat checking, or if warped more than 0. 020 inch, plate must be refaced or replaced. (When refacing pressure plate, remove only sufficient metal to obtain a smooth flat surface.) When pressure plate thickness becomes less than 1.141 inch, replacement is nec essary. 6. If flywheel is warped or heat checked and surface is refinished, maintain the 1.188 inch dimension between disc surface and bolting face for proper release lever adjustment. No more than 0.070 inch maxi mum may be removed by grinding. 7. Inspect driven disc assembly for cracks, loose rivets, worn splines, warped or dished condition. If cracked, or hub splines are worn excessively, replace disc assembly. If facings are worn down nearly even with countersunk, facing-retaining rivet heads and provided assembly is in otherwise good condition, it may be rebuilt. 8. Pilot bearing should be removed, clean ed and checked each time clutch or engine is removed. Discard bearing if balls or races are chipped or scored. After in spection, hand-pack bearing with clutch pilot bearing grease and install bearing in flywheel. Tap into place with shielded side toward clutch. Use only the recommended pilot bearings specified. These bearings will function without premature failure where slight misalignment exists between engine and transmission. After bearing is properly installed, pack the entire cavity in back of the bearing with the same specified clutch pilot grease. 2. Place pressure springs in position on pressure plate, as shown in Figure 4-12. CAUTION To prevent damage to the bearing seal when the transmission is as sembled to the engine, the space occupied by the main driving pinion pilot must not be filled with grease. See Figure 4-11. FLYWHEEL CLUTCH PILOT BALL BEARING (SNAP-RING TYPE) WITH BUILT-IN GREASE SEAL HANO-PACK CAVITY EXACTLY AS SHOWN AFTER BALL BEARING INSTALLATION. CENTRAL AREA MUST BE CLEAR OF GREASE BEARING SNAP-RING COUNTERBORE Figure 4 -11. Cut-away View of Clutch Pilot Bearing Grease Reservoir Correctly Packed Reassembly 1. Mount release lever assemblies on pressure plate. Set pressure plate as sembly on three equally spaced steel blocks 3/8 inch thick, on bed of arbor or drill press, plate side down. Figure 4-12. Assembling Clutch 3. Lay cover plate over springs, being sure that all springs are seated on bosses of pressure plate, and around indentations on inside of cover. 4. If pressure plate was refaced, it will be necessary at assembly, to add shims under each pressure spring equal to total metal removed. 5. Compress assembly slowly, aligning lever adjusting screws with threaded holes in cover plate. (The indentations inside cover, should enter the spaces between drive bosses on pressure plate freely.) With screwdriver, thread ends of adjust ing screws into cover evenly, until screws protrude about 1/2 inch. Hold assembly compressed, while placing locknuts in posi tion, but do not tighten. 6. To facilitate installation on flywheel, place wood blocks approximately 3/8 inch thick, between the tops of release levers and inner rim of cover plate. (Be sure these stay in position as all tension is released). 7. Insert the three spring retention tools (J26451), through cover and bottom in tapped holes in pressure plate (center hole of each five series in cover). With pres- 4-9 3. While holding spring retention tool screws, back off tool nuts alternately, mak ing one turn at a time. When spring is entirely relieved, back out the three tool screws. 4. Remove clutch cover and springs. If heat-insulating washers are removed from pressure plate spring pockets, retain them for reassembly. The eyebolts need not be removed, unless inspection reveals distor tion or loose fit on pins. Inspection and Repair 1. Remove all traces of dirt and oil with a suitable safety solvent. Inspect parts care fully for cracks, distortion or excessive wear as described in the following steps. 2. jf cover is cracked or distorted, re place. Tack-weld loose spring cups (on covers having this construction) replace worn or loose ball-fulcrums. Replace loose or bent release lever spring pins. 3. Replace springs if cracked or defec tive. Check all springs on a spring tester. Replace all that do not meet specifications. 4. Replace thrust washer if worn, bent or defective. 5. Replace worn release levers, springs and ball seats. Check levers with a straight edge and 11/16 inch ball (J26453) as il lustrated, in Figure 4-14 and if bent so that dimension (1) is more 11/32 inch when measured at a point where distance (2) is 2-1/2 inch, replace the lever. Figure 4-14. Checking Release Lever for Bend 6. If pressure and intermediate plates are scored, heat checked, or warped more than 0.020 inch, they must be replaced or re faced. Remove only enough metal to ob tain a smooth flat surface. Finish with a light cut and polish with emery cloth. When thickness (1) becomes less than the worn limit given in specifications, the plate must be replaced. Measure at outer spring pock et as shown in Figure 4-15. Measuring at inner pocket is not accurate if pressure plate is dished. If cleft lugs are worn, cracked or distorted, replace the plate. The intermediate plate features a double set of drive slots for increased service life. At clutch installations after rebuild, it is re commended that the set with less wear be used. Replace eyebolts if they are dis torted, have worn threads or keyways. (Mil Figure 4-15. Pressure Plate Thickness Dimension 7. If flywheel is warped or heat checked and surface is refinished, maintain the 2.797 inch dimension between disc sur face and bolting face for proper release lever adjustment. See Figure 4-16. No more than 0.070 inch maximum may be removed by grinding. Figure 4-16. Flywheel Rubbing Surfaceto-Clutch Cover Bolting Surface Dimension Intermediate plate drive pins should be inspected for abnormal wear. When pins have been removed to permit flywheel machining, or require replace ment, squareness between flywheel friction and pin drive faces must be maintained at installation. A positioning tool will assist in establishing necessary alignment. Suitable for this purpose, will be a slotted steel block 4 inches long, 2-1/2 inches wide and 1-1/2 inches thick. One 2-1/2 inches x 4 inches face should be ground for maximum flatness, as it will constitute the major working surface. A 3/16 inch x 45 degree chamfer along all edges of this face will tend to prevent burrs that would affect accuracy. See Figure 4-17. 4-11 3-16 X <5` CHAMFER, Figure 4-17. Drive Pin Positioning Tool Midway between ends of the 4 inch length, a 0.627 to 0. 628 inch wide slot 1-i inch deep should be machined through the 1-1/2 inch thickness. The slot must be exactly square with the ground face for it will determine flywheel to drive pin head alignment. A half -inch drift pin clearance hole, drilled from the side opposite, and intersecting with, the slot will complete the tool. Hole centerline should be 7/8 inch from the ground face, so that driving force will be centered over the head. Magnetizing the block will minimize movement during driv ing and lessen possibility of marring fly wheel face. In use, the threaded portion of the pin is inserted in the flywheel hole. The position ing tool slot is placed over the drive head, with the ground surface held flat against the flywheel friction face. The pin is then driven until fully seated. 8. Inspect driven disc assembly for cracks, loose rivets, worn splines, warped or dished condition. If cracked, or hub splines are worn excessively, replace disc assembly. If facings are worn down nearly even with countersunk facing-retaining rivet heads and assembly is in otherwise good condition, it may be rebuilt. 9. Pilot bearing should be removed, clean ed and checked each time clutch or engine is removed. Discard bearing if balls or races are chipped or scored. After inspec tion, hand-pack bearing with clutch pilot bearing grease and install bearing in fly 4-12 wheel. Tap into place with shielded side toward clutch and snap ring seated in coun terbore. All current Mack-made engine flywheels have been manufactured by boring the clutch pilot bearing hole straight-through and counterboring a recess to provide proper positioning for the snap ring type pilot bearings now in use. Old bearings without a snap ring cannot be used in new throughbored flywheels. ; CAUTION Do not install anew snap ring bear ing in an old flywheel without re moving the snap ring and dis carding. In old flywheels without the counterbore, the snap ring would position the bearing too far rearward, which would result in early bearing failure and consider able damage to costly components. Use only the recommended snap ring type bearings specified. These bearings will function with out premature failure where slight misalignment exists between en gine and transmission. After bearing is properly installed, pack the entire cavity in back of the bearing with the same specified clutch pilot grease. CAUTION To prevent damage to the bearing seal when the transmission is as sembled to the engine, the space occupied by the main driving pinion pilot must not be filled with grease. See Figure 4-18. Before assembling the clutch, a positive wear check should be made to insure that it will provide maximum disc wear. This check will uncover any interference that might prevent full release lever travel and allow corrections to be made before the clutch is assembled. Place the pressure plate assembly and cov er (without springs) into position as shown in Figure 4-19, making sure that shims of the correct thickness (0. 250) are inserted between cover and spacer (J26458). In stall each release lever and while pressing firmly on the fulcrum, measure distance (1) inboard end of lever is raised above cover. Correct height is 3-11/32 inches. Remove any interference that prevents ob taining this dimension. CRANKSHAFT FLYWHEEL CLUTCH PILOT BALL BEARING (SNAP-RING TYPE) WITH BUILT-IN GREASE SEAL HAND-PACK CAVITY EXACTLY AS SHOWN AFTER BALL BEARING INSTALLATION. CENTRAL AREA MUST BE CLEAR OF GREASE BEARING SNAP-RING COUNTERBORE Figure 4-18. Cut-away View of Clutch Pilot Bearing Grease Reservoir Correctly Packed NOTE If pressure plate and intermediate plate were refaced, insert wash ers into the spring cups of a thick ness equal to the metal removed from the pressure plate and inter mediate plate. Shellac the wash ers in place to facilitate retention. 3. Place the cover in position, align the springs in the pockets. Bottom the screws of the three spring retention tools into the threaded holes of the pressure plate and bring the tool nuts down snugly against the tool bracket. Tighten the tool nuts alter nately, one turn at a time, guiding the pres sure plate lugs into the clutch cover holes until the inside face of the cover is 1.1875 inch from the face of the pressure plate. Special tool (J26458) and a 1/16 inch spacer (J26448) , is used to facilitate obtaining this dimension. See Figure 4-20. NOTE If the intermediate driving plate is worn or has been machined, the consequent reduction in thickness will produce the same effect as worn clutch discs when the clutch assembly is installed in a vehicle. In an extreme case, one-half the available release collar wear travel may be used up before the vehicle is put back into service. Reassembly 1. Remove the shims used for the wear check. Lightly lubricate pivot ball bush ing, fulcrum groove, eyebolt pin and in board end of release lever with clutch lever grease. 2. Place the pressure plate on a surface plate with the spring pockets of the pres sure plate up. Place heat-insulating wash ers and the springs in the pressure plate spring pockets. To compensate for this condition, shims of appropriate thickness must be inserted be tween cover and spacers (J26458) while the clutch is adjusted. Measure thickness of the intermediate driving plate which will be used with clutch being adjusted and com pare with new thickness as shown in speci fications. If plate is 0.010 inch or more below new thickness, secure shims equal in thickness to amount of metal removed and insert them between clutch cover and spacers (J26458) at equally spaced in tervals. See Figure 4-20. 4. Place the clutch release levers on the ball fulcrums and eyebolt shanks. Place the lever springs on the spring pins with the small diameter against the release levers. Place the spring washers in position, com- 4-13 1. Clutch Cover 11. Double Torsion 2. Release Cover Anti-Rattle Spring 3. Release Lever 12. Thrust Washer Pin Clamp 4. Needle Bearings 13. Lever Thrust 5. Release Lever Washer Ring Yoke 14. Pressure Plate 6. Yoke Leaf 15. Helical, Main Spring Spring 7. Lever Adjust 16. Heat Insulator ing Nut Ring 8. Adjusting Nut 17. Driven Disc Lock Plate Assembly 9. Lock Plate Lock 18. Facing Rivet Screw 19. Driven Disc 10. Yoke Clevis Pin Facings Figure 4-21. Sectional View of CL-58 Series Clutch Figure 4-22. Removing Lever Adjusting Nut Lock Plates main spring insulator washers from pres sure plate bosses. NOTE Do not remove the six lever anti rattle springs from the cover un less replacement is necessary. 4. Lay pressure plate on bench and with a soft metal drift, drive hardened lever pins out of pressure plate drive lugs to free re lease levers. With a pair of pliers, remove cotter pin from each lever yoke clevis pin and then press out each yoke clevis pin by hand. CAUTION When removing levers from pres sure plate drive lugs and lever yoke, be very careful not to lose any of the small uncaged needle rollers. Inspection and Repair Remove all traces of dirt and oil with a suitable safety solvent. Inspect parts care fully for cracks, distortion or excessive wear as described in the following steps. 1. Replace springs if cracked or defective. Check all springs on a spring tester. Re place all that do not meet specifications. 2. If pressure plate is scored, heat check ed, or warped more than 0.025 inch, it must be replaced or refaced. Remove only enough metal to obtain a smooth flat surface. No more than 0.070 inch maximum may be re moved by grinding. 4-15 3. Inspect clutch release lever tips and clevis pin holes for excessive wear. Make sure levers are not bent. Replace where necessary. 4. Inspect release lever yokes for con dition of threads. Slight thread damage may be cleaned up with a three-cornered Swiss file. Replace lever yokes if clevis pin holes are elongated. 5. Check clevis pins and lever pins for wear. Replace if wear is excessive. Check lever slotted thrust washer ring for exces sive wear. Replace if slots are excessive ly worn. 6. Check lever needle roller bearings for wear. If flats are such that rollers slide rather than roll, replace rollers. 7. Inspect driven disc assembly for cracks, loose rivets, worn splines, warped or dished condition. If cracked, or hub splines are worn excessively, replace disc assembly. If facings are worn down nearly even with countersunk facing-retaining rivet heads and provided assembly is in otherwise good condition, it may be rebuilt. 8. If flywheel is warped or heat checked and surface is refinished, maintain dimen sions shown in Figure 4-23 between disc surface and bolting face for proper release lever adjustment. No more than 0. 070 inch maximum may be removed by grinding. tion, hand-pack bearing with clutch pilot bearing grease specified and install bear ing in flywheel. Tap into place with shield ed side toward clutch and snap ring seated in counterbore. Use only the recommended snap ring type bearings. These bearings will function with out premature failure where slight mis alignment exists between engine and trans mission. After bearing is properly installed, pack the entire cavity in back of the bearing with the same specified clutch pilot grease. CAUTION To prevent damage to the bearing seal when the transmission is as sembled to the engine, the space occupied by the main driving pinion pilot must not be filled with grease. See Figure 4-24. FLYWHEEL CLUTCH PILOT BALL BEARING (SNAP-RING TYPE) WITH BUILT-IN GREASE SEAL HAND-PACK CAVITY EXACTLY AS SHOWN AFTER BALLBEARING INSTALLATION. CENTRAL AREA MUST 8E CLEAR OF GREASE BEARING SNAP-RING COUNTERBORE Figure 4-23. Flywheel Rubbing Surfaceto-Clutch Cover Bolting Surface Dimension 9. Pilot bearing should be removed, clean ed and checked each time clutch or engine is removed. Discard bearing if balls or races are chipped or scored. Afterinspec 4-16 n-ui Figure 4-24. Cut-away View of Clutch Pilot Bearing Grease Reservoir Correctly Packed Reassembly 1. Apply a light coat of clutch lever grease on the loose needle bearings and install rollers in each pin hole of levers. When bearings are installed, apply additional grease to each assembled bearing group. 2. Spread a thin coat of lever grease on the two rubbing flats of each lever and on all yoke rubbing surfaces. Center lever srtszr1*4 gp- 1. Pressure Plate 2. Return Spring 3. Pivot Pin 4. Spring Clip 5. Lever 6. Adjusting Ring 7. Snap Ring 8. Release Sleeve Ring 9. Release Sleeve Retainer 1>SI 10. Spring Pivot 11. Pressure Spring 12. Flywheel Ring 13. Adjusting Ring Lock 14. Bolt & Lock Washer Assy 15. Release Bearing & Bearing Assy 16. Driven Rear Disc 17. Intermediate Plate 18. Driven Front Disc Figure 4-33. Exploded View AS-1550 Series Clutch Assembly Removal and Disassembly A suitable "sling" or transmission jack should be used to properly support and main tain the engine/transmission alignment when removing or installing a transmission on an engine. DO NOT let the rear end of the transmission drop downand hang unsupported in the splined hubs of the clutch discs to avoid bendingor distortingthe frictiondiscs. Disconnect the external linkage from the clutch release arm to permit the release yoke to turn up and pull free of the release bearing thrust pads. 1. Prior to actual clutch removal, assemble a clutch disc aligning tool to the driven disc and release bearing assembly. It is important that two 3/4 inch blocks of wood as shown in Figures 4-34 and 4-35 be inserted between the clutch release bearing housing and clutch flywheel ring as the clutch mounting bolts are loosened around the fly wheel. These blocks will relieve the heavy internal spring load, preventing cocking and bending within the clutch and insure easy re moval of remaining mounting bolts. 2. When all bolts have been removed, slide clutch assembly back and off using caution to keep aligning tool in place to retain discs and intermediate plate. 3. Carefully remove aligning tool, rear disc, intermediate plate and front disc. 4-30 i i f L Remaining uuuu i-lXXC <. - Figure 4-43. Removing Retainer Clip Inspection and Repair Clean all parts thoroughly with a suitable safety solvent. Many clutches are replaced as a preventative maintenance item at low mileage during re pairs of the transmission or engine. Before the Clutch Assembly is replaced, the unit should be inspected for the following items: REMAINING CLUTCH LIFE M3-74 Driven Discs Inspect disc assembly for cracks, loose ri vets, worn splines, warped or dished condi tion. Re-straighten if dished or warped beyond 0.015 inch maximum runout. Re place if hub is cracked, or splines are worn excessively. 1. Heat cracks in the pressure plate. 2. Excessive wear in all drive slots. 3. Broken springs. 4. Dry or damaged release bearing. 5. Broken intermediate plate. 6. Excessive driven disc hub spline wear. 7. Burned facings. 8. Excessive wear on drive pins or inter mediate plate slots. If the preceding inspection shows clutch parts to be in good condition, use the fol lowing chart to determine the approximate remaining clutch life (by measuring the thickness of the rear driven disc assembly). Replace facings if they are glazed, scored, worn down to rivet heads, burned, or if contaminated with grease or oil. The driven discs use high-quality asbestos facings riveted to the steel disc. They may be furnished as rigid type disc or damper type. Used discs can be reworked in the field by drilling out the rivets to remove old facings. Use the correct size drill when re moving old rivets to avoid enlarging holes in disc. Use proper facings and a star set an vil to reline used discs. Find thickness of rear disc on column to left; follow curve on right, then drop this point down to read percent of clutch life re maining. Ceramic friction material, a combination of metal and ceramic, is used in producing round or trapezoidal buttons which are riveted to steel discs. These clutch 4-33 discs, available with either rigid or damper hubs, offer many advantages for heavy-duty applications. Reworking these discs in the field is not recommended because the ceram ic buttons must be assembled and ground to hold thickness as well as squareness with splines. Super-duty discs have six trapezoidal cer amic buttons and are available with rigid or damper hubs. These discs are thinner than standard discs while the intermediate plate is thicker. This combination of more ceramic buttons and thicker Intermediate plate provides longer life and increased torque capacity. A super-duty kit consisting of two driven discs and an intermediate plate is available for converting a standard Angle-Spring clutch into a super - duty clutch. It is very im portant that the kit be installed as a unit and that Its components never be intermixed with standard components. Flywheel Ring Inspect the flywheel ring for cracks. Re place if cracks are visible. Check slots for Indentation caused by wear of pressure plate driving lugs. See Specification Chart for slot limits. Inspect bolt circle face and pilot for nicks and burrs due to removal or handling. Re move burrs with file to insure proper seat ing and squareness when clutch is mounted to flywheel. pressure plate. Smooth and flat pressure plate surfaces must be used for satisfactory clutch life. Check drive lugs for wear per Specification Chart. Intermediate Plate Inspect friction surfaces of intermediate plate for heat checks, scoring or distortion. If friction surface is badly scored, heat checked, warped or dished in excess of 0.010 inch, resurface or replace with new intermediate plate. Smooth and flat inter mediate plate surfaces must be used for sat isfactory clutch life. Inspect driving slots of intermediate plate for wear per Specifi cation Chart. Release Levers Inspect levers for excessive wear at points of contactwith pressure plate, release sleeve retainer, and pivot pin. If levers are bent or worn, replace with new levers. It is good preventive maintenance to replace levers during clutch rebuild. Release Sleeve Retainer Inspect for wear in lever groove and internal splines. Refer to specifications for driving slot clearance between flywheel ring drive slots and release sleeve retainer drive lugs. Adjusting Ring Check pivot pin holes for wear. Clearance may not exceed 0.010 inch between pin and hole. Inspect for cracks; replace if cracks are visible. Pressure Plate Inspect fulcrum for wear. If wear exceeds 0.015 inch, remachine. See Specification Chart for maximum rework. Inspect friction surface of pressure plate for scoring, burning, heat checking or distor tion. If friction surface is badly scored, heat checked, warped or dished in excess of 0.010 inch, resurface or replace with new 4-34 Spring Pivots Inspect for cracks; if visible, replace. Release Sleeve Sub-Assembly Check bushing for excessive wear. Check bearing diameter for tight fit. Refer to Specifications Chart and replace if nece ssary. Release Bearing and Sleeve Assembly It is recommended that the release bearing and sleeve assembly be replaced as a unit at the time of clutch rebuild. Assemblies are available as service replacement items. The pressure plate is driven by means of driving lugs extending into mating slots of the flywheel ring (cover). The intermediate plate is driven by drivepins located in the engine flywheel. NOTE Drive pin alignment gage, Lipe Tool No. T-CT1, is available for checking squareness of drive pins to friction face of flywheel. Depressing the clutch pedal pulls the release bearing toward the transmission. The re lease bearing being connected to the release levers thus retracts the pressure plate from contact with the driven disc assembly, there by relieving the pressure on the intermediate plate and the forward driven disc assembly which disengages the clutch. Releasing the clutch pedal allows the release bearing assembly to move toward the engine permitting the pressure plate to move to ward the flywheel gripping the discs, causing engagement. After the pins are installed and properly squared, try the intermediate plate for fit over the pins. With new pins and a new in termediate plate, there should be from 0.006 inch to 0.014 inch clearance. Try the plate in different positions and select the position which provides the greatest freedom of move ment. Mark the plate for location to the fly wheel. Lock the drive pins in place with the socket head or Allen set screws. Driven discs are marked, "Pressure Plate Side" and "Flywheel Side", to indicate their proper positions. Install as indicated. Clutch Installation Before installing the clutch on the flywheel, check for free fit of cover assembly to fly wheel and flywheel alignment before proceed ing with installation. See Figures 4-80, 481, 4-82 and 4-83. Be sure that intermediate drive pins are a press fit in holes in flywheel rim and that the heads are perfectly square to the friction surface. Drive pins must be square to pro vide proper clearance for the drive slots in the intermediate plate. A machinist's square and feeler gage may be used to check for squareness. The cover assembly may now be installed on the flywheel but, before tightening cap screws, install an aligning shaft through the two hubs and into pilot bearing. SAE Grade 8 cover capscrews may now be tightened progressively around the flywheel using 45 lbs. ft. of torque. Remove the three hold down bolts from cover before removing splined aligning shaft or disc assemblies may fall out of position.