785D OEM Off-Highway Truck Power Train Caterpillar

Assembly Procedure

Note: Inspect the O-ring seals, the seals, and the gaskets. Replace the O-ring seals, the seals, and the gaskets that are worn or damaged.

Note: Lubricate the O-ring seals lightly with the lubricant that is being sealed.

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Illustration 1	g00559343

1. Install O-ring seals (140) on each plug (139).
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   Illustration 2	g00559341

2. Install four plugs (139) on manifold (103).
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   Illustration 3	g00559885

3. Use Tooling (B) (not shown) to install lip seal (129) in manifold (103).
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   Illustration 4	g00559339

4. Install O-ring seal (137) onto each plug (134). Install O-ring seal (136) on plug (131).
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   Illustration 5	g00559338

5. Install O-ring seal (135) on nipple (132).
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   Illustration 6	g00559337

6. Install nipple (132) and dust cap (132) on manifold (103). Install plug (134) and five plugs (131) on manifold (103).
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   Illustration 7	g00559888

7. Use Tooling (B) (not shown) to install bearing (138) on manifold (103).
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   Illustration 8	g00559333

8. Install two O-ring seals (128) and O-ring seal (127) on cartridge assembly (126). Repeat this process for the two remaining cartridge assemblies.
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   Illustration 9	g00559332

9. Install three cartridge assemblies (126) on manifold (103). Tighten three cartridge assemblies (126) to a torque of 80 ± 5 N·m (59.01 ± 3.69 lb ft).
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   Illustration 10	g00559331

10. Install three coils (125), the three washers, and three locknuts (124). Tighten three locknuts (124) to a torque of 9 ± .5 N·m (6.64 ± 0.37 lb ft).
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    Illustration 11	g00559330

11. Install O-ring seal (123) onto wire harness (119).
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    Illustration 12	g00559328

12. Install wire harness (119), cover (122), two washers, and two bolts (121) on manifold (103).
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    Illustration 13	g00559327

13. Install transmission gear switch (118) of the EPTC II and two bolts (120) on manifold (103).

14. Connect wire harness (119) to transmission gear switch (118) of the EPTC II.
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    Illustration 14	g00559326

15. Install gasket (117) onto manifold (103).
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    Illustration 15	g00559325

16. Install cover (112), four bolts (114), and six bolts (113) on manifold (103). Install elbow (115) and O-ring seal (116) onto manifold (103).
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    Illustration 16	g00559302

17. Install four plugs (109) and four O-ring seals (110).

18. Install five O-ring seals (111) and O-ring seal (108) onto manifold (103).
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    Illustration 17	g00559300

19. Install retaining ring (107) onto coupler (101).
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    Illustration 18	g00559299

20. Install six O-ring seals (106) onto three tubes (104). Install two O-ring seals (105) on tube (102).
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    Illustration 19	g00559298

21. Install tube (102) and three tubes (104) in position on manifold (103).
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    Illustration 20	g00559296

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    Personal injury can result from being struck by parts propelled by a released spring force. Make sure to wear all necessary protective equipment. Follow the recommended procedure and use all recommended tooling to release the spring force.

22. Use clean SAE 30 oil on slug (98). Install ball (100), spring (99), and slug (98) in spool (95). Use Tool (A) (not shown) to install snap ring (97).
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    Illustration 21	g00559292

23. Use clean SAE 30 oil on spool (95). Install shims (96) in the end of spool (94). To determine the amount of shims that are required, refer to Testing and Adjusting, SENR1489, "Transmission Hydraulic Control Pilot Pressure - Test and Adjust".

24. Install spring (97) and spool (95) into the valve body.
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    Illustration 22	g00559290

25. Install two dowels (93) on the top and the bottom of support (92). Install the dowels so the ends extend 6.5 ± .25 mm (0.256 ± 0.009 inch) above the surface.
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    Personal injury can result from being struck by parts propelled by a released spring force. Make sure to wear all necessary protective equipment. Follow the recommended procedure and use all recommended tooling to release the spring force.

26. Position support (92), as shown. Install two bolts (94).
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    Illustration 23	g00584705

27. If necessary, install pin (91) and pin (90) into rotary selector spool (82). Use holes (X) as a reference to assemble pin (90). The pin (91) should protrude −.8 ± .25 mm (0.0315 ± 0.0098 inch) above the surface.
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    Illustration 24	g00584701

28. Install screen filter (88) into rotary selector spool (82). Tighten screen (88) to a torque of 6.1 ± .7 N·m (53.99 ± 6.19 lb in).

29. Install cam (86) into rotary selector spool (82).

30. Install spring pin (87) through rotary selector spool (82) and cam (86). Install spring pin (87) 1.0 ± .5 mm (0.04 ± 0.02 inch) below the surface of rotary selector spool (82).

31. Install two spring pins (89) into spring pin (87) so that the slots that are in spring pins (89) are 180 ± 20 degrees from the slot that is in spring pin (87).
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    Illustration 25	g00559901

32. Apply clean SAE 30 oil on rotary selector spool (82). Install rotary selector spool (82) into the valve body.
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    Illustration 26	g00559902

33. Install washer (85) and bolt (84). Washer (85) and bolt (84) hold the rotary selector spool in position. Tighten bolt (84) to a torque of 30 ± 7 N·m (22.1 ± 5.2 lb ft).

34. Install two springs (81), two retainers (83), and two bolts (80) on the support. Tighten bolt (80) to a torque of 30 ± 7 N·m (22.1 ± 5.2 lb ft).

    Note: Be certain that the side of each spring (81) is 4.5 ± .5 mm (0.18 ± 0.02 inch) away from the side of the selector valve body.

35. Loosen bolts (94) in order to ensure that the rollers in springs (81) are centered with the notches in the cam. When the rollers are centered, tighten bolts (94). Tighten bolt (94) to a torque of 30 ± 7 N·m (22.1 ± 5.2 lb ft).
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    Illustration 27	g00559903

36. Use Tooling (B) (not shown) to install bearing (79) in actuator body (64). Install bearing (79) so the end extends 3.0 ± .5 mm (0.12 ± 0.02 inch) above the surface of actuator body (63).
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    Illustration 28	g00559924

37. Install O-ring seal (72) on plug (71). Install valve (73) and plug (69). Install the flat end of valve (73) first.

38. Install O-ring seal (75) on plug (74). Install valve (76) and plug (74). Install the flat end of valve (76) first.
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    Illustration 29	g00559925

39. Install vane (70) and two bolts (69) in the actuator body. Do not tighten bolts (69). Be certain that notch (Y) on the vane is in the position that is shown.
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    Illustration 30	g00559285

40. Use clean SAE 10 oil on all the surfaces of rotor (68). Install rotor (68) in actuator (64).
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    Illustration 31	g00559978

41. Use Tooling (B) (not shown) to install bearing (67) in cover (66). Install bearing (67) 1.3 ± .25 mm (0.051 ± 0.009 inch) below the surface of cover (66).
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    Illustration 32	g00559280

42. Install cover (66) on the actuator body. Install two bolts (65). Bolts (65) hold cover (66) in position. Tighten bolts (65) to a torque of 30 ± 4 N·m (22.1 ± 2.9 lb ft).

43. Tighten bolts (69) (not shown) to a torque of 15 ± 3 N·m (11.1 ± 2.2 lb ft).

    Note: The rotor must freely rotate 300 degrees.

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    Illustration 33	g00559979

44. Install the actuator on the selector valve body. Larger groove (Y) in rotor (68) must align with the head end of the pin on rotary selector spool (82).
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    Illustration 34	g00559277

45. Install two bolts (63). Bolts (63) hold actuator (64) in position on the selector valve. Tighten bolts (63) to a torque of 30 ± 4 N·m (22.1 ± 2.9 lb ft).
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    Illustration 35	g00559275

46. Install O-ring seal (60) on seat (59). Use clean SAE 30 oil on O-ring seal (60).
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    Personal injury can result from being struck by parts propelled by a released spring force. Make sure to wear all necessary protective equipment. Follow the recommended procedure and use all recommended tooling to release the spring force.

47. Install spring (62), ball (61), and seat (59) in spool (56). Use Tool (A) (not shown) to install snap ring (58).
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    Illustration 36	g00559980

48. Install spring (57) and spool (56) into the valve body.
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    Illustration 37	g00584648

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    Personal injury can result from being struck by parts propelled by a released spring force. Make sure to wear all necessary protective equipment. Follow the recommended procedure and use all recommended tooling to release the spring force.

49. Use bolts (50) and (52) to install valve (54), O-ring seal (53), O-ring seal (51), and cover (55) onto the valve body. Position cover (55) onto the valve body. Install bolts (50) and (52) that hold cover (55) in place.

    Note: During the installation of valve (54) in cover (55), position the end with the ball against the pin.

50. Tighten bolts (50) and bolts (52) to a torque of 30 ± 7 N·m (22.1 ± 5.2 lb ft).
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    Illustration 38	g00559268

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    Personal injury can result from being struck by parts propelled by a released spring force. Make sure to wear all necessary protective equipment. Follow the recommended procedure and use all recommended tooling to release the spring force.

51. Install valve (44), spring (43), retainer (42), and spiral ring (41) in spool (45).

52. Install spacers (46) and (47) in the end of spool (45). Use clean SAE 30 oil on the outside diameter of spool (45).
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    Personal injury can result from being struck by parts propelled by a released spring force. Make sure to wear all necessary protective equipment. Follow the recommended procedure and use all recommended tooling to release the spring force.

53. Use two bolts (39) to install spring (49), spring (48), spool (45), and cover (40) on the selector control valve. Tighten two bolts (39) to a torque of 30 ± 7 N·m (22.1 ± 5.2 lb ft).
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    Illustration 39	g00559242

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    Personal injury can result from being struck by parts propelled by a released spring force. Make sure to wear all necessary protective equipment. Follow the recommended procedure and use all recommended tooling to release the spring force.

54. Install ball (32), spring (33), and retainer (34) in spool (13). Use Tool (A) (not shown) to install snap ring (35) in the end of spool (13).
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    Illustration 40	g00559177

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    Illustration 41	g00559174

55. Use the following procedure in order to assemble station "D":

    Note: Station "D" is for the signal oil to the dual stage relief valve.

    Note: Use clean SAE 30 oil on all the surfaces of spool (13) and slug (12).

    1. Install the following items into housing (23): piston (31), piston (17), spring (15), stop (14), spool (13), slug (12) and spring (11).

    2. Use two screws (24) in order to install housing (23) onto the pressure control valve body.
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    Illustration 42	g00564073

    Note: The pressure control valve for each clutch is marked on the pressure control valve body at location (U). The letter is also stamped on housing (23).

    Note: Station "A" is for the No. 2 clutch. Station "B" is for No. 1 clutch. Station "C" is for No. 3 clutch. Station "E" is for No. 4 clutch. Station "F" is for No. 5 clutch. Station "G" is for No. 6 clutch.

56. Use the following procedure to assemble the stations:

    Note: Refer to Table 2 for installation purposes.

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    Table 2

    Station	Thickness of Orifice (21)	Color of the Plug	Inner Spring (19)	Outer Spring (15)
    A	2.54 mm (0.100 inch)	Blue	Green	Green
    B	4.58 mm (0.180 inch)	Yellow	Light Blue	Green
    C	2.54 mm (0.100 inch)	Red	Light Blue	Green
    E	2.54 mm (0.100 inch)	Green	Orange	Green
    F	0.60 mm (0.024 inch)	Yellow	Yellow	Green
    G	6.6 mm (0.26 inch)		Green	Green

    1. Use clean SAE 30 oil on all the surfaces of spool (13) and slug (12). Install slug (12) in spool (13).

    2. Install spring (11), spool (13), and stop (14) in the pressure control valve.

    3. Install O-ring seal (26) on plug (25). Install plug (25) in body (23). Install O-ring seal (28) on plug (27). Install plug (27) in body (23). Install O-ring seal (30) on plug (29). Install plug (29) in body (23).

       Note: Plug (27) contains an orifice for most of the stations. Station "G" has a regular plug. The orifice that is in the plugs for the other stations will vary. The orifice sizes may be different. Some plugs also contain a screen.

57. Use clean SAE 30 oil on O-ring seal (22). Install O-ring seal (22), orifice (21), and spring (20) in body (23).

58. Use clean SAE 30 oil on all the surfaces of pistons (17) and (18). Place piston (17) in piston (18).

59. Install shims (16), springs (15), and springs (19) in the end of piston (17).

    Note: A piston is provided in the place of spring (19) on station "D".

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    Personal injury can result from being struck by parts propelled by a released spring force. Make sure to wear all necessary protective equipment. Follow the recommended procedure and use all recommended tooling to release the spring force.

60. Install piston (18) in body (23). Use two screws (24) to install body (23) on the pressure control valve.
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    Illustration 43	g00559264

61. Use clean SAE 30 oil on piston (35). Install piston (35) in the pressure control valve. Install washer (37) and bolt (36). Washer (37) and bolt (36) hold piston (35) in place.
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    Illustration 44	g00564031

62. Install plate (8) and bolt (9) on manifold (10). Tighten bolt (9) to a torque of 30 ± 4 N·m (22.1 ± 2.9 lb ft).
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    Illustration 45	g00564029

63. Install selector and pressure valve (5). Install eight bolts (6) and bolt (7). Tighten eight bolts (6) and bolt (7) to a torque of 30 ± 4 N·m (22.1 ± 2.9 lb ft).
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    Illustration 46	g00564028

64. Install pressure control valve (4) on selector and pressure valve (5).
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    Illustration 47	g00564027

65. Install cover (1), four bolts (2), and bolt (3) on pressure control valve (4). Tighten four bolts (2) to a torque of 30 ± 4 N·m (22.1 ± 2.9 lb ft). Tighten bolt (3) to a torque of 48 ± 4 N·m (35.4 ± 2.9 lb ft).

66. Test the control valve. Refer to Specifications, SENR1487, "Transmission Hydraulic Control" for the correct procedures.

End By:

1. Install the transmission hydraulic control. Refer to Disassembly and Assembly, "Transmission Hydraulic Control - Install".