988G Wheel Loader Power Train Caterpillar

Disassembly Procedure

Start By:

1. Remove the torque converter. Refer to Disassembly and Assembly, "Torque Converter - Remove" for the machine that is being serviced.

2. Remove the transmission oil pump. Refer to Disassembly and Assembly, "Transmission Oil Pump - Remove" for the machine that is being serviced.

3. Remove the torque converter outlet relief valve. Refer to Disassembly and Assembly, "Relief Valve (Torque Converter Outlet) - Remove" for the machine that is being serviced.

4. Remove the modulating valve for the torque converter impeller clutch. Refer to Disassembly and Assembly, "Modulating Valve (Torque Converter Impeller Clutch) - Remove" for the machine that is being serviced.

5. Remove the modulating valve for the torque converter lockup clutch. Refer to Disassembly and Assembly, "Modulating Valve (Torque Converter Lockup Clutch) - Remove" for the machine that is being serviced.

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Illustration 1	g00673844

1. Place the torque converter assembly on cribbing. The weight of the torque converter assembly is 545 kg (1200 lb).
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   Illustration 2	g00660841

2. Remove speed sensor (1).
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   Illustration 3	g00665406

3. Remove bolt (2) and retainer (3).
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   Illustration 4	g00665411

4. Remove O-ring seal (4) and yoke (5).
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   Illustration 5	g00665412

5. Remove eleven bolts (6) and the washers.
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   Illustration 6	g00665414

6. Install Tooling (A) to housing assembly.

7. Attach a suitable lifting device and lifting chains to Tooling (A).

8. Use M12 x 1.75 forcing screws in order to separate housing assembly from the torque converter.

9. Use the suitable lifting device in order to remove housing assembly. The weight of the housing assembly is 285 kg (630 lb).
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   Illustration 7	g00660846

10. Remove eight bolts (7) and retainer (8).
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    Illustration 8	g00660847

11. Remove seal (9) from retainer (8).
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    Illustration 9	g00660849

12. Remove gasket (10).

13. Remove O-ring seal (11) and (12).
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    Illustration 10	g00673879

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    Illustration 11	g00673880

14. Position torque converter assembly onto the side, as shown.

15. Remove six bolts (13) and cover (14).
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    Illustration 12	g00673881

16. Remove two bolts (15), retainer (16), and washer (17).
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    Illustration 13	g00673882

17. Use Tooling (B) in order to push the shaft out of the bearing.
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    Illustration 14	g00673883

18. Position torque converter assembly upright, as shown.

19. Install Tooling (C) to shaft assembly (18).

20. Attach a suitable lifting device and a sling to Tooling (C).

21. Use the suitable lifting device in order to remove shaft assembly (18). The weight of shaft assembly (18) is 17 kg (38 lb).
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    Illustration 15	g00673886

22. Use a suitable press in order to remove bearing (19) and seal carrier (20) from inner shaft (18).
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    Illustration 16	g01061064

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    Illustration 17	g01061071

23. Remove 36 bolts (21), and washers (22). Do not remove two bolts (25) at this time.
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    Illustration 18	g00673887

24. Install Tooling (D).

25. Attach a suitable lifting device and lifting slings to Tooling (D).

26. Use the suitable lifting device in order to remove carrier assembly (23). The weight of carrier assembly (23) is 132 kg (290 lb).
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    Illustration 19	g00673888

27. Place carrier assembly (23), as shown.

28. Remove stator (24).
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    Illustration 20	g01060995

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    Illustration 21	g01061000

29. Remove retaining ring (29) and plate (28) from stator (24). Remove ring (26) (not shown), and plate (27) (not shown) from the other side of stator (24).

30. Use a suitable press in order to remove adapter (30) from stator (24).
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    Illustration 22	g00674499

31. Remove spacer (33).
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    Illustration 23	g00674501

32. Remove bearing (34).

33. Remove the plate and the ring below bearing (34).
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    Illustration 24	g00674503

34. Remove retaining ring (35).
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    Illustration 25	g00674504

35. Use two persons in order to remove impeller (36). The weight of impeller (36) is 29 kg (65 lb).
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    Illustration 26	g00674505

36. Remove race (37) from impeller (36).
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    Illustration 27	g00674506

37. Remove twelve bolts (38) and the washers.

38. Remove impeller (36) from adapter assembly (39).
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    Illustration 28	g00674507

39. Remove bearing (40).

40. Remove the plate and the ring below bearing (40).
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    Illustration 29	g01061078

41. Remove two bolts (25) and plate (41).

    Note: Bolts (25) are on the underside of plate (41).

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    Illustration 30	g00674510

42. Remove two friction discs (42) and one wear plate.
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    Illustration 31	g00674512

43. Remove piston (43).
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    Illustration 32	g00674516

44. Remove seal (44) from piston (43).
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    Illustration 33	g00674514

45. Install Tooling (E) to housing assembly (45).

46. Attach a suitable lifting device and slings to housing assembly (45).

47. Use the suitable lifting device in order to remove housing assembly (45). The weight of housing assembly (45) is 45 kg (100 lb).
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    Illustration 34	g00674519

48. Remove twelve bolts (46) and gear (47) from housing assembly (45).
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    Illustration 35	g00674520

49. Remove race (48) from gear (47).
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    Illustration 36	g00674521

50. Remove eight bolts (49) and sleeve (50).
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    Illustration 37	g00674522

51. Remove seal (51) from sleeve (50).
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    Illustration 38	g00674523

52. Remove seal (52).

53. Remove two seals (53).

54. Remove retaining ring (54).
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    Illustration 39	g00674524

55. Use a hammer and a punch in order to remove pin (55).
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    Illustration 40	g00674721

56. Use Tooling (F) in order to remove ring carrier (56).
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    Illustration 41	g00674722

57. Use Tooling (G) in order to remove bearing (57).
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    Illustration 42	g00674723

58. Remove bearing (58).

59. Remove the plate and the ring below bearing (58).
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    Illustration 43	g00674725

60. Use appropriate equipment to turn the housing onto the opposite side.

61. Remove O-ring seal (59) and two plugs (60).
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    Illustration 44	g00674726

62. Use suitable cribbing in order to support the turbine and hub assembly. Place the cribbing inside the housing assembly.

63. Use Tooling (H) in order to remove the hub from bearing (61).
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    Illustration 45	g00674727

64. Remove bearing (61).
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    Illustration 46	g00674744

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    Illustration 47	g00674747

65. Remove 24 bolts (62) and hub (63) from turbine (64).

66. Remove clutch adapter (65).
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    Illustration 48	g00674748

67. Remove retaining ring (66) and plate (67).
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    Illustration 49	g00674750

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    Illustration 50	g00674788

68. Remove two wear plates (68) and two friction discs (69).
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    Illustration 51	g00674790

69. Remove piston (70).

    Note: It may be necessary to use shop air under pressure of 621 kPa (90 psi) to remove piston (70).

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    Illustration 52	g00674791

70. Remove seal (71) from piston (70).

    Note: The following steps are used for the removal and disassembly of the pump drives.

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    Illustration 53	g00674951

71. Remove seven bolts (72).
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    Illustration 54	g00674952

72. Install two forcing screws and Tooling (J).

73. Attach a suitable lifting device and lifting slings to Tooling (J).

74. Use the suitable lifting device in order to remove adapter (73). The weight of adapter (73) is 30 kg (65 lb).

    Note: If necessary, use forcing screws to separate adapter (73) from the housing.

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    Illustration 55	g00674953

75. Remove two O-ring seals (74) from adapter (73).
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    Illustration 56	g00674954

76. Remove race (75) and seal (76) from adapter (73).
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    Illustration 57	g00674955

77. Remove gear assembly (77).
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    Illustration 58	g00674956

78. Use Tooling (F) in order to remove bearing (78) from gear assembly (77).
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    Illustration 59	g00674957

79. Remove retaining ring (79) and adapter (80) from gear assembly (77).
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    Illustration 60	g00674959

80. Remove retaining ring (81) from adapter (80). Remove plate (82).
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    Illustration 61	g00674960

81. Use Tooling (F) in order to remove bearing (83) from gear assembly (77).
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    Illustration 62	g00674961

82. Remove shim pack (84) and race (85).
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    Illustration 63	g00674980

83. Remove three bolts (86) and cover (87).
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    Illustration 64	g00674982

84. Remove O-ring seal (88) from cover (87).
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    Illustration 65	g00674983

85. Remove bolt (89) and the washer.

86. Remove idler gear shaft (90).
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    Illustration 66	g00674984

87. Remove idler gear assembly (91).
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    Illustration 67	g00674986

88. Remove two bearings (92) and ring (93) from idler gear assembly (91).
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    Illustration 68	g00674987

89. Remove four bolts (94) and block (95).
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    Illustration 69	g00674989

90. Remove five O-rings (96) and three plugs (97).

91. Repeat steps 71 through 90 in order to remove the remaining pump adapter.