301.6C and 301.8C Mini Hydraulic Excavators Machine Systems Caterpillar

Assembly Procedure

Note: Cleanliness is an important factor. Before assembly, all parts should be thoroughly cleaned in cleaning fluid. Allow the parts to air dry. Wiping cloths or rags should not be used to dry parts. Lint may be deposited on the parts which may cause later trouble. Inspect all parts. If any parts are worn or damaged, use new parts for replacement.

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Illustration 1	g01173004

1. Install cover (110) on studs (111) .

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Illustration 2	g01172996

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Illustration 3	g01172995

2. Install plug (108) and the O-ring seal.

3. Install spool (107), spring (106), O-ring seal (105), and plug (104) .

4. Install check valve (103), check valve (109), and the O-ring seals.

5. Refer to Steps 51 and 52 for the assembly of valve (102) .

6. Install valve assembly (101) .

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Illustration 4	g01172919

7. Install plug (99) and the O-ring seal.

8. Install check valve (96), check valve (100), and the O-ring seals.

9. Refer to Steps 51 and 52 for the assembly of valve (95) .

10. Install O-ring seals (97) and (98) .

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Illustration 5	g01172909

11. Install valve assembly (94) .

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Illustration 6	g01172888

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Illustration 7	g01172885

12. Install O-ring seals (91) and (92) .

13. Refer to Steps 41 and 42 for the assembly of valve (93) .

14. Install valve assembly (87) .

15. Install O-ring seals (88) and (90) .

16. Install plug (89) and the O-ring seal.

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Illustration 8	g01172860

17. Install plugs (85) and the O-ring seals.

18. Install check valve (83), check valve (86), and the O-ring seals.

19. Refer to Steps 51 and 52 for the assembly of valve (82) .

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Illustration 9	g01172848

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Illustration 10	g01172847

20. Install plug (79) and the O-ring seal.

21. Refer to Steps 41 and 42 for the assembly of valve (81) .

22. Install O-ring seals (78) and (80) .

23. Install valve assembly (74) .

24. Install O-ring seals (75), (76), and (77) .

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Illustration 11	g01172819

25. Install plug (69) and the O-ring seal.

26. Install check valve (67), check valve (72), and the O-ring seals.

27. Refer to Steps 51 and 52 for the assembly of valve (73) .

28. Install O-ring seals (70) and (71) .

29. Install valve assembly (68) .

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Illustration 12	g01172807

30. Install plug (62) and the O-ring seal.

31. Install check valve (60), check valve (65), and the O-ring seals.

32. Refer to Steps 41 and 42 for the assembly of valve (66) .

33. Install O-ring seals (63) and (64) .

34. Install valve assembly (61) .

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Illustration 13	g01172806

35. Install plugs (58) and the O-ring seals.

36. Install plug (57) and the O-ring seal.

37. Install check valve (56) and the O-ring seal.

38. Refer to Steps 51 and 52 for the assembly of valve (55) .

39. Install valve assembly (59) .

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Illustration 14	g01172722

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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.

40. Install plug (48) and the O-ring seal.

41. Install spool (47), O-ring seal (46), wiper seal (45), plate (44), retainer (43), spring (42), retainer (41), bolt (40), housing (39), and bolts (38) .

42. Install O-ring seal (51), wiper seal (52), plate (53), and bolt (54) .

43. Install O-ring seals (49) and (50) .

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Illustration 15	g01172721

44. Install valve assembly (37) .

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Illustration 16	g01172692

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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.

45. Install plug (30) and the O-ring seal.

46. Install spool (29), adapter (28), O-ring seal (27), wiper seal (26), spacer (25), housing (24), spring (23), retainer (22), housing (21), and bolts (20) .

47. Install O-ring seal (33), wiper seal (34), plate (35), and bolts (36) .

48. Install O-ring seals (31) and (32) .

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Illustration 17	g01172690

49. Install valve assembly (19) .

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Illustration 18	g01172670

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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.

50. Install plug (13) and the O-ring seal.

51. Install spool (12), retainer (11), spring (10), retainer (9), bolt (8), housing (6), and bolts (7) .

52. Install O-ring seal (14), housing (15), and bolts (16) .

53. Install O-ring seals (17) and (18) .

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Illustration 19	g01172654

54. Install valve assembly (5) .

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Illustration 20	g01172652

55. Install O-ring seal (4) on cover (1) .

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Illustration 21	g01172649

56. Install cover (1) and nuts (2) .

57. Install tube assembly (3) .

End By: Install the main control valve. Refer to Disassembly and Assembly, "Main Control Valve - Install".