Instruction Sheet Date: Bulletin #: Subject: Purpose: Model Numbers: Serial Numbers: Recipients: 16 October 425D Gearbox Drive Update Kit Installation To instruct dealers in installation 425D All serial numbers All Lastec Distributors Part Number Description Quantity 028790 Kit, 425D Gearbox Drive Update 028339 Mount Wldmt, Fnt Eng / Gearbox 1 041810 Bushing, 5/8x7/8x1/2 Super Oil Lite 2 F05010-96 Nut, 5/8-11 Jam Nyl Lock 1 045509 Kit, Drive Tensioner Arm 1 028308 Pivot Wldmnt, Idler 1 F05010-185 Nut, 5/8-11 Flexloc 1 041707 Spacer, 1 OD x 5/8 ID x 1-5/8 Lng 1 041701 Idler Pulley, 421D 1 F05009-37 Bolt, 5/8-11x3 HH Gr5 1 041188 Spring, 3/4x5 1/2x.095 Wire 1 F05006-76 Bolt, 5/16-18x1 1/2 HH GR5 FT 2 F05010-58 Nut, 5/16-18 Nylok Hex 6 028345 Bracket, Spring Drive Belt Tensioner 1 F05006-1 Bolt, 5/16-18x1 HH Gr2 2 F05011-17 Washer, 5/16 SAE Flat 2 018818 Spring, 3/4x5x.105 Ext 1 028348 Bracket, Mount Gearbox LH 1 028349 Bracket, Mount Gearbox RH 1 028580 Shim, 425HD Gear Box 2 F05007-124 Bolt, 3/8-16x2 HH Gr5 4 F05010-10 Nut, 3/8-16 Hex Nyl Lock 4 F05007-118 Bolt, 3/8-16x3/4 HH Gr5 4 F05011-4 Washer, 3/8 Split Lock 4 Instruction Sheet 1 041743 Kit, Hydro Belts,Gearbox, Poly-V 1 028082 Belt, BX34 1 041702 Belt, Hydro BX35 1 041734 Belt, Poly Rib 34.06 K10 1 041739 Pulley & Armature Assy, Poly-V 1 Page 1 of 7
028629 Sheave, Poly-V 5.16 OD SDS 1 018732 Plate, Drive Motor Front Mount 1 019303 Spring, 1x7x.148 Wire 325E-98 2 F05089-5 Tie Wrap, 5/16 x 15 UV Black 6 F05007-123 Bolt, 3/8-16x1 ¼ HH Gr5 1 F05007-125* Bolt, 3/8-16x2 1/2 HH Gr5 1 F05010-124 Nut, 3/8-16 Half Nyloc 2 IS-0054* Inst Sht, Poly-V Belt Kit 1 *Not used for this procedure. This procedure is long. Please read through the entire instruction sheet before proceeding. Retain all hardware for reassembly unless specifically stated otherwise. Instructions: All directions referring to Right, Left, Front and Back are in regards to a seated operator facing the forward position. 1. Ensure that the articulator is parked on level ground. 2. Turn the unit to the off position and remove the key. 3. Jack up rear of unit and secure it properly according to the safety requirements of the method of jacking used. Firewall Removal 4. Remove the hydraulic filter and bracket from the firewall. Retain all hardware. 5. Remove air hose from the air filter attached to the firewall. 6. Unfasten four bolts holding the firewall to the roll bar and set aside for later procedures. Retain all hardware. Tip: Replace retained hardware into the holes from which they came in order to keep track of all fasteners and hardware. Gearbox Belt Loosening 7. Remove the deck drive belt from the gearbox. 8. Remove the fasteners used to secure the gearbox to the gearbox mounts. Do not retain hardware. 9. Raise the gearbox enough to remove the clutch belt. Electrical connections Clutch and Gearbox Removal Tip: Clutch must be removed before gearbox will pass through the framework. 10. Unplug the electrical connections to the clutch. 11. Remove the front clutch bolt and washers. Retain hardware. 12. Slide the clutch off of the crankshaft. A gear puller may be necessary to remove clutch and associated sheaves. Retain all hardware, including shaft key. 13. Loosen sockhead cap screws from the gearbox side mounts if necessary. Slide gearbox up from motor mount and remove. Do not retain hardware. Page 2 of 7
Hydraulic Belt Removal 14. If not previously done, jack up rear of unit and secure it properly according to the safety requirements of the method of jacking used. 15. Remove the five lug bolts from the tire assembly and retain hardware. Remove tire. 16. Remove nut holding the hydraulic pump spring to the frame within the wheel well. 17. Detach spring from frame side. A spring puller may be required for this step. 18. Repeat steps 15 through 17 on the opposite side of mower. 19. Hydraulic pumps are now loosened and may be pivoted enough to remove the belts from the engine. Motor Mount Removal Springs 20. Secure engine with engine hoist. Be sure to follow safety instructions for attaching the hoist to the engine. 21. Remove all 5 side bolts on each side of the motor mount that fit onto the engine. Retain hardware. 22. Remove both mounts on each side of the engine, holding the engine to the frame. Retain all the hardware, including the rubber bushings. 23. Remove two rear engine mounts to the frame. Retain all hardware, including the rubber bushings. 24. Remove throttle cable from handle area. Retain all hardware. 25. Lift engine up from frame in order to slide motor mount out from underneath the engine. Motor Mount bolts Throttle cable Side Engine mounts Rear Engine mounts New Motor Mount Assembly 26. With parts supplied from the kit, insert bushings 041810 into both ends of the idler orifice on the motor mount. 27. Insert idler armature 028308 and attach the nut F05010-185. 28. Place bolt F05009-37, idler pulley 041701, spacer 041707, and nut F05010-96 on the armature as shown below. 29. Assemble spring 041188, bolt F05006-76 and nuts F05010-58 on armature as shown below. Page 3 of 7
041188 F05010-58 F05010-185 F05006-76 041707 F05010-96 028339 041810 F05009-37 041701 028308 041810 30. Slide the assembled motor mount in place under the engine. 31. To assist in alignment on frame motor mounts, loosely reattach the rear engine bolts first. 32. Lower the engine slowly while aligning the mounts to the framework. 33. Reinstall the four side bolts to the engine. Using lock tight, tighten all engine bolts to 75 ft-lbs. 34. Replace all four bushings, fender washers, nuts, and bolts on frame. Apply lock tight and torque to 75 ft-lbs. 35. Replace the rear motor mounts and hardware. 36. Replace throttle cable from whence it came. Replacing Hydraulic Pump Faceplate 37. On the right side hydraulic pump, remove the spring and hardware at the bottom of the existing faceplate. Retain hardware. 38. Remove the (2) bolts located in the split taper bushing that secures the pulley to the pump. 018732 F05007-123 F05010-124 019303 39. Insert the same (2) bolts into the opposite holes on the bushing. 40. Tighten each bolt equally until the bushing becomes dislodged from the pulley. Retain hardware. 41. Remove the key located on the pump shaft. Retain hardware. Page 4 of 7
42. Remove the old pulley from the pump. 43. Remove upper bolt, washer, and nut from the pump and faceplate. Retain hardware. 44. Remove upper bolt, washer, nut, and spacer from the frame and faceplate. Retain hardware. 45. Remove old faceplate from pump and replace with the faceplate 018732 from the kit. 46. Replace upper bolt, washer, and nut retained in step 67 to the pump and faceplate. Do not tighten at this time. 47. Replace lower bolt and nut retained in step 61 to hold faceplate to pump. Do not tighten at this time. 48. Replace upper bolt, washer, nut, and spacer retained in step 68 to the frame and faceplate. Do not tighten at this time. 49. Replace sheave and split taper bushing, maintaining alignment with the key. 50. Replace right hydraulic pump belt 041702 on pulley. Align the new right belt and the pulleys from the engine and pump. 51. When aligned, tighten down the bushing bolts. 52. Tighten the bolts of the upper and lower connections of the faceplate to the pump 53. Secure the frame bolt connecting the faceplate to the frame. Some slight play should remain in this pivot area. 54. Replace new left hydraulic belt 028082 at this time. 55. With parts from the kit, attach the new spring 019303 to the lowest point on the faceplate as shown. 56. With a spring puller, replace the new spring 019303 to the stud on the frame and replace the nut. 57. Replace the tire on the right side. 58. Repeat steps 56 through 57 on the left side. Assembling Gearbox 59. Remove existing gearbox mounts from the side of the gearbox. Discard. 60. Remove the (3) bolts located in the split taper bushing that secures the pulley to the gearbox. 61. Insert the same (3) bolts into the opposite holes F05007-118 on the bushing. 62. Tighten each bolt equally until the bushing becomes dislodged from the pulley. 63. Remove the split tapered bushing from the pulley. 64. Remove the key located on the gearbox shaft and save for later use. 65. Remove the old pulley from the gearbox and discard. 66. Assemble gearbox sheave 028629 to the gearbox. F05011-4 028348 F05010-10 F05007-124 028580 028629 028349 F05007-124 028580 F05010-10 67. Assemble the key used previously into the key way located on the gearbox shaft. 68. Reassemble the split tapered bushing onto the gearbox shaft. Do not tighten at this time. The bushing will be tightened later in the assembly. 69. Remove top pulley from gearbox, and retain all parts for later replacement. 70. Place the gearbox on the motor mount with new hardware from the kit. The fit is tight and awkward maneuvering of the gearbox may be required. Do not tighten at this point. Replacing the Clutch and Gearbox F05011-4 F05007-118 Page 5 of 7
71. Remove the old stator pulley assembly from the clutch. The old pulley assembly must be taken out at an angle to accommodate the electro-magnet. 72. Assemble stator pulley assembly 041739 from the kit to the clutch. The new stator pulley assembly must be assembled at an angle to accommodate the electro-magnet. 73. Place the clutch onto the crankshaft. Ensure that the clutch stop bracket is inserted into the groove located on the topside of the clutch. 74. Secure with the previously used clutch nut and bolt. 75. Torque to 50 ft-lbs. 76. Secure the electrical connections with the tie wraps F05089-5 provided in the kit. 77. Place the Poly-V belt 041734 in place between the clutch and the gearbox. 78. Using a straight edge, align the gearbox pulley with the clutch pulley. Use shims 028580 if necessary to achieve proper alignment. 79. Tighten the gearbox mounting bolts. 80. When aligned, secure the gearbox pulley by tightening the (3) bolts located in the bushing. Torque to 109 in-lbs. 81. After tightening the gearbox, verify the alignment between the gearbox pulley and the clutch pulley again. In the event that realignment is needed, loosen the gearbox and position it until the pulleys are aligned. Verify, again, that the gearbox and clutch pulleys are aligned. Repeat this step as necessary until the pulleys are aligned. 82. Replace the upper sheave on the gearbox. 041739 Straight edge Page 6 of 7
Idler Bracket Assembly 83. On the firewall, drill two holes according to the illustration to the right. 84. Attach bracket 028345 with the hardware in the kit. 85. Replace the firewall to the original position on the roll bar. 86. Reattach the hydraulic filter to the firewall. 87. Reattach the air hose to the air filter. 88. With spring 041188, attach the idler armature to the firewall bracket. Final Assembly 89. Lower unit off of jack stands. 90. Reattach drive belt to mowing decks and gearbox. 91. Close hood and seat pan. F05010-58 028345 F05006-1 F05011-17 F05010-58 F05006-76 End of Bulletin Page 7 of 7