793C Off-Highway Truck/Tractor Power Train Caterpillar

Disassembly Procedure

Start By:

1. Remove the torque converter. Refer to Disassembly and Assembly, "Torque Converter - Remove".

2. Remove the transmission and torque converter pump. Refer to Disassembly and Assembly, "Gear Pump (Torque Converter and Transmission) - Remove".

3. Remove the torque converter inlet relief valve. Refer to Disassembly and Assembly, "Relief Valve (Torque Converter Inlet) - Remove and Install".

4. Remove the torque converter outlet relief valve. Refer to Disassembly and Assembly, "Relief Valve (Torque Converter Outlet) - Remove and Install".

5. Remove the lockup clutch and synchronizing valve of the torque converter. Refer to Disassembly and Assembly, "Lockup Clutch and Synchronizing Valve - Remove and Install".

6. Remove the torque converter screen. Refer to Disassembly and Assembly, "Screen (Torque Converter) - Remove".

7. If necessary, remove the two sensors for the Wiggins Service Center.

Note: For information on reusability of the components of the differential and bevel gear, refer to Guideline for Reusable Parts and Salvage Operations, SEBF8254, "Removing Wear from Seal Grooves in Seal Ring (Stator) Carrier Assemblies for Off-Highway Trucks". Refer to Guideline for Reusable Parts and Salvage Operations, SEBF8005, "Repair of Pump Drive Gears for Torque Converters". Refer to Guideline for Reusable Parts and Salvage Operations, SEBF8087, "Cast Aluminum Stator Wheels for Torque Converters".

Note: For information on product updates, refer to Guideline for Reusable Parts and Salvage Operations, SEBF8342, "Transmission, Torque Converter, and Finial Drive Updates for Off-Highway Trucks".

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Illustration 1	g00511038

1. Remove six bolts (1) and six washers. Remove cover gasket (2) from torque converter housing (3).

2. Remove four bolts (4) and four washers. Remove cover (5) and the screen assembly from torque converter housing (3).
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   Illustration 2	g00511041

3. Remove O-ring seal (6) from cover (5).
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   Illustration 3	g00511043

4. Remove six bolts (7) and six washers. Remove baffle (8) from torque converter housing (3).
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   Illustration 4	g00511044

5. Remove O-ring seal (9) from baffle (8).
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   Illustration 5	g00511046

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   Illustration 6	g00511047

6. Remove 17 bolts (10) from the torque converter.

7. Use Tool (A) and a suitable lifting device to remove torque converter housing (3) from the torque converter. The weight of the torque converter housing is 329 kg (725.3 lb).
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   Illustration 7	g00511048

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   Illustration 8	g00511049

8. Remove eight bolts (11), eight washers, eight nuts (12), and mud flap (13) from the support.
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   Illustration 9	g00511051

9. Remove four bolts (14) and four washers. Remove support (15) from torque converter housing (3).
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   Illustration 10	g00511052

10. Remove eight bolts (16), eight washers, and plate (17) from torque converter housing (3).
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    Illustration 11	g00511053

11. Remove gasket (18), two oil level sight gauges (19), and two grommets (20) from torque converter housing (3).
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    Illustration 12	g00511056

12. Remove two plugs (21) and O-ring seals from torque converter housing (3).
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    Illustration 13	g00511057

13. Remove orifice plug (22) from torque converter housing (3).
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    Illustration 14	g00511059

14. Remove two plugs (23) and two O-ring seals from torque converter housing (3).
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    Illustration 15	g00511060

15. Remove dowel (24) from torque converter housing (3).
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    Illustration 16	g00511062

16. Remove two O-ring seals (25) from the torque converter.
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    Illustration 17	g00511063

17. Remove bolt (26) and retainer (27) from the torque converter.
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    Illustration 18	g00511064

18. Remove O-ring seal (28) from the torque converter.
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    Illustration 19	g00511065

19. Remove yoke assembly (29) from the torque converter.
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    Illustration 20	g00511086

20. Use Tool (A) and a suitable lifting device to place the torque converter on a suitable stand. The torque converter weighs approximately 625 kg (1377.9 lb).
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    Illustration 21	g00511087

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    Personal injury or death can occur from heavy components falling during removal or installation. Properly support the component with a suitable lifting device during removal or installation.

    Note: The torque converter must be supported at areas (X) when bolts (32), plate (33), and spring washer is removed. The turbine shaft and the carrier can fall if the torque converter is not properly supported.

21. Remove Tool (A), ten remaining bolts (30) and the washers from the torque converter.
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    Illustration 22	g00511088

22. Use two 3/8 inch - 16 NC forcing screws to remove flywheel pilot (31) from the torque converter.
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    Illustration 23	g00511089

23. Remove three bolts (32). Remove plate retainer (33) and the spring washer from the output shaft.
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    Illustration 24	g00511091

24. Mark the position of rotating housing (34) and the impeller for installation purposes.
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    Illustration 25	g01014469

25. Install Tool (B) in the tapped hole at the end of the hub.
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    Personal injury or death can occur from heavy components falling during removal or installation. Properly support the component with a suitable lifting device during removal or installation.

    Note: Be certain that Tool (B) is installed in the hub to prevent the hub and the turbine from falling.

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    Illustration 26	g00511094

26. Remove 30 bolts (35) and 30 washers.

27. Use Tool (A) and a suitable lifting device to remove rotating housing (34) and the clutch housing from the torque converter. The combined weight of rotating housing (34) and the clutch housing is 227 kg (500.5 lb).
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    Illustration 27	g00511096

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    Illustration 28	g00511097

28. Turn over rotating housing (34). Remove ten bolts (36) and the ten washers from support (37). Bolts (36) are 12 point head bolts.
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    Illustration 29	g00511098

29. Slowly remove two bolts (38) and the two washers. Remove thrust race (39) from support (37).

    Note: There are springs under pressure behind thrust race (39).

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    Illustration 30	g00511100

30. Remove eight springs (40) and support (37) from turbine (41).
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    Illustration 31	g00511101

31. Use Tool (D) and a suitable press to remove bearing sleeve (42) from support (37).
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    Illustration 32	g00511102

32. Remove two dowels (43) from support (37).
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    Illustration 33	g00511104

33. Use two persons to remove turbine (41) from rotating housing (34). Turbine (41) weighs approximately 27 kg (59.5 lb).
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    Illustration 34	g00511105

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    Illustration 35	g01014472

34. Remove 26 bolts (44) and 26 washers.

35. Use Tool (A) and a suitable lifting device to remove rotating housing (34) from clutch housing (46). Rotating housing (34) weighs approximately 59 kg (130.1 lb).
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    Illustration 36	g00511107

36. Turn over rotating housing (34). Remove pipe plug (45) from rotating housing (34).
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    Illustration 37	g00511108

37. Turn over clutch housing (46) and hub (47) to allow four friction discs (48) and three clutch plates (49) (not shown) to fall free from clutch housing (46). Remove Tool (B) from hub (47).
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    Illustration 38	g01014473

38. Use Tool (A) and a suitable lifting device to lift clutch housing (46) by approximately 25 mm (0.98 inch). Use a soft hammer to drive hub (47) from clutch housing (46).
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    Illustration 39	g00511112

39. Use three forcing screws to remove ring carrier (48) from hub (47).

40. Remove locking ring (49) from hub (47).
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    Illustration 40	g00511113

41. Remove seal ring (50) from ring carrier (48).
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    Illustration 41	g01014474

42. Use Tool (A) and a suitable lifting device to remove clutch piston (51) from clutch housing (46). Clutch piston (46) weighs approximately 30 kg (66.1 lb).
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    Illustration 42	g00511116

43. Remove seal ring (52) from clutch piston (51).
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    Illustration 43	g00511117

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    NOTICE
    Pay attention to the orientation of the bearings. The bearings must be properly installed. If the bearings are improperly installed, premature failure of the bearings will occur.

44. Remove two ball bearings (53) and (54) from clutch housing (46).
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    Illustration 44	g00511118

45. Remove wear sleeve (55). Remove seal ring (56) and plug (57) from clutch housing (46).
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    Illustration 45	g00511119

46. Remove needle bearing (58) from bearing support (59).
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    Illustration 46	g01014475

47. Use Tool (E) and a suitable lifting device to remove converter stator (60).
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    Illustration 47	g01014478

48. Remove Tool (E) and remaining five bolts (61). Remove bearing support (59) from converter stator (60).
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    Illustration 48	g00511126

49. Use Tool (D) and a suitable press to remove the bearing sleeve (62) (not shown) from support (59).
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    Illustration 49	g00511127

50. Remove the 24 freewheel rollers (63). Remove roller cage (64) and two springs (65) from converter stator (60).

    Note: Two springs (65) are under pressure.

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    Illustration 50	g00511128

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    Illustration 51	g00511130

51. Use Tool (D) and a suitable press to remove race (66) from converter stator (60).
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    Illustration 52	g00511132

52. Remove retaining ring (67) from converter stator (60).

    Note: For information on reusability of the components of the differential and bevel gear, refer to Guideline for Reusable Parts and Salvage Operations, SEBF8087, "Cast Aluminum Stator Wheels for Torque Converters".

53. For a minimum of twenty minutes, raise the temperature of stator (60) and freewheel cam (68) in an oven to a maximum temperature of 148 °C (298.4 °F). Use Tool (D) and a suitable press to remove freewheel cam (68) from converter stator (60).
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    Illustration 53	g00511133

54. Use Tool (D) and a suitable press to remove bearing sleeve (69) (not shown) from race (66).
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    Illustration 54	g00511135

55. Remove needle bearing (70) from impeller hub (71).
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    Illustration 55	g01014480

56. Use Tool (A) and a suitable lifting device to remove impeller (72) and drive flange (73) as a unit. The combined weight of impeller (72) and drive flange (73) is 84 kg (185.2 lb).
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    Illustration 56	g00511137

57. Remove eight bolts (74) and impeller hub (71) from impeller (72).
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    Illustration 57	g00511138

58. Remove thrust race (75) from impeller hub (71).
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    Illustration 58	g00511139

59. Remove O-ring seal (76) from impeller hub (71).
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    Illustration 59	g00511141

60. Use two people to remove impeller (72) from drive flange (73). Impeller (72) weighs approximately 25 kg (55.1 lb).
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    Illustration 60	g00511142

61. Remove O-ring seal (77) from drive flange (73).
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    Illustration 61	g00511143

62. Turn over drive flange (73). Remove twelve bolts (78) and pump drive gear (79) from drive flange (73).

    Note: For information on reusability of the components of the differential and bevel gear, refer to Guideline for Reusable Parts and Salvage Operations, SEBF8005, "Repair of Pump Drive Gears for Torque Converters".

63. Use Tool (D) and a suitable press to remove sleeve (80) from drive flange (73).
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    Illustration 62	g00511145

64. Remove six bolts (81) and split washer (82). Remove freewheel race (83) from stator carrier (84).
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    Illustration 63	g00511146

65. Turn over the stator carrier. Remove 12 bolts (85), the 12 washers, and distributor (86) from stator carrier (84).
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    Illustration 64	g00511147

66. Remove gasket (87) from stator carrier (84).
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    Illustration 65	g00511148

67. Drill three small holes in lip seal (88). Use Tool (G) to remove lip seal (88) from distributor (86).
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    Illustration 66	g00511150

68. Remove sensor rotor (89), plug (90), and the O-ring seal from distributor (86).
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    Illustration 67	g00511151

69. Use Tool (F) to lift output shaft (91) and stator carrier (84) off the stand by approximately 13 mm (0.5 inch). The combined weight of output shaft (91) and stator carrier (84) is 79 kg (174.2 lb).

70. Use a soft hammer to remove stator carrier (84) from output shaft (91). Stator carrier (84) weighs approximately 41 kg (90.4 lb). Output shaft (91) weighs approximately 38 kg (83.8 lb).
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    Illustration 68	g00511152

71. Remove two seal rings (92) from ring carrier (93). Remove seal ring (94) from ring carrier (95).
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    Illustration 69	g00511154

72. Use a suitable press to remove ring carrier (93), ball bearing (96), and ring carrier (95) from output shaft (91).
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    Illustration 70	g00511155

73. Remove two seal rings (97) from stator carrier (84).
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    Illustration 71	g00511157

74. Use a screwdriver to remove snap ring (98) from stator carrier (84).
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    Illustration 72	g00511159

75. Use two screwdrivers to remove inner bearing (99) from stator carrier (84).

    Note: For information on reusability of the components of the differential and bevel gear, refer to Guideline for Reusable Parts and Salvage Operations, SEBF8254, "Removing Wear from Seal Grooves in Seal Ring (Stator) Carrier Assemblies for Off-Highway Trucks".