303.5D CR, 304D CR, 305D CR and 305.5D CR Mini Hydraulic Excavators Machine Systems Main Control Valve - Assemble Caterpillar

Assembly Procedure

Note: Cleanliness is an important factor. Thoroughly clean all parts in cleaning fluid before assembly. 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	g01225240

1. Install check valve (80) and check valve (79) into inlet control valve (73) .

2. Install plug (78) and the O-ring seal into inlet control valve (73) .

3. Install O-ring seal (77) and O-ring seal (76) into inlet control valve (73). Install O-ring seal (75) into inlet control valve (73) .

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Illustration 2	g01225230

4. Install rods (74) into inlet control valve (73) .

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Illustration 3	g01225226

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Improper assembly of parts that are spring loaded can cause bodily injury. To prevent possible injury, follow the established assembly procedure and wear protective equipment.

5. Refer to Step 44 and refer to Step 45 for travel control valve (72) .

6. Refer to Step 48 through Step 51 for travel control valve (72) .

7. Position travel control valve (72) onto the valve bank.

8. Refer to Step 53 for travel control valve (72). Install plate (71) onto travel control valve (72) .

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Illustration 4	g01225223

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Improper assembly of parts that are spring loaded can cause bodily injury. To prevent possible injury, follow the established assembly procedure and wear protective equipment.

9. Refer to Step 44 and refer to Step 45 for travel control valve (70) .

10. Refer to Step 48 through Step 51 for travel control valve (70) .

11. Position travel control valve (70) onto the valve bank.

12. Refer to Step 53 for travel control valve (70). Install plate (69) onto travel control valve (70) .

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Illustration 5	g01224411

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Improper assembly of parts that are spring loaded can cause bodily injury. To prevent possible injury, follow the established assembly procedure and wear protective equipment.

13. Refer to Step 44 and refer to Step 45 for blade control valve (68) .

14. Refer to Step 48 through Step 51 for blade control valve (68) .

15. Position blade control valve (68) onto the valve bank.

16. Refer to Step 53 for blade control valve (68). Install plate (67) onto blade control valve (68) .

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Illustration 6	g01224379

17. Refer to Step 44 and refer to Step 45 for boom control valve (48) .

18. Install check valve (66) and check valve (65) onto boom control valve (48) .

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Illustration 7	g01224354

19. Install check valve (64) onto housing (57) .

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Illustration 8	g01224337

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Improper assembly of parts that are spring loaded can cause bodily injury. To prevent possible injury, follow the established assembly procedure and wear protective equipment.

20. Install the following items into boom control valve (48) : washer (63), spring (62), spring retainer (61), O-ring seal (60), O-ring seal (59), O-ring seal (58), housing (57) and bolts (56) .

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Illustration 9	g01224028

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Improper assembly of parts that are spring loaded can cause bodily injury. To prevent possible injury, follow the established assembly procedure and wear protective equipment.

21. Install the following items into boom control valve (48) : spool (49), washer (50), spring (51) and spring retainer (52) .

22. Install O-ring seal (53) onto cap (55) .

23. Position cap (55) onto boom control valve (48) and install bolts (54) .

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Illustration 10	g01223988

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Improper assembly of parts that are spring loaded can cause bodily injury. To prevent possible injury, follow the established assembly procedure and wear protective equipment.

24. Position boom control valve (48) onto the valve bank.

25. Refer to Step 53 for boom control valve (48). Install plate (47) onto boom control valve (48) .

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Illustration 11	g01223929

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Improper assembly of parts that are spring loaded can cause bodily injury. To prevent possible injury, follow the established assembly procedure and wear protective equipment.

26. Refer to Step 44 and refer to Step 45 for work tool control valve (46) .

27. Refer to Step 48 through Step 51 for work tool control valve (46) .

28. Position work tool control valve (46) onto the valve bank.

29. Refer to Step 53 for work tool control valve (46). Install plate (45) onto work tool control valve (46) .

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Illustration 12	g01223839

30. Refer to Step 44 and refer to Step 45 for bucket control valve (42) .

31. Install check valve (44) and install check valve (43) onto bucket control valve (42) .

32. Refer to Step 48 through Step 51 for bucket control valve (42) .

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Illustration 13	g01223814

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Improper assembly of parts that are spring loaded can cause bodily injury. To prevent possible injury, follow the established assembly procedure and wear protective equipment.

33. Position bucket control valve (42) onto the valve bank.

34. Refer to Step 53 for bucket control valve (42). Install plate (41) onto bucket control valve (42) .

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Illustration 14	g01223654

35. Refer to Step 44 and refer to Step 45 for stick control valve (38) .

36. Install check valve (40) and check valve (39) onto stick control valve (38) .

37. Refer to Step 48 through Step 51 for stick control valve (38) .

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Illustration 15	g01223566

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Improper assembly of parts that are spring loaded can cause bodily injury. To prevent possible injury, follow the established assembly procedure and wear protective equipment.

38. Position stick control valve (38) onto the valve bank.

39. Refer to Step 53 for stick control valve (38). Install plate (37) onto stick control valve (38) .

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Illustration 16	g01223561

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Improper assembly of parts that are spring loaded can cause bodily injury. To prevent possible injury, follow the established assembly procedure and wear protective equipment.

40. Refer to Step 44 and refer to Step 45 for swing control valve (36) .

41. Refer to Step 48 through Step 51 for swing control valve (36) .

42. Position swing control valve (36) onto the valve bank.

43. Refer to Step 53 for swing control valve (36). Install plate (35) onto swing control valve (36) .

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Illustration 17	g01224420

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Improper assembly of parts that are spring loaded can cause bodily injury. To prevent possible injury, follow the established assembly procedure and wear protective equipment.

44. Install piston (33) and spring (34). Install O-ring seal (32) .

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Illustration 18	g01223610

45. Position flange (31) onto the control valve and install bolts (30) .

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Illustration 19	g01223583

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Improper assembly of parts that are spring loaded can cause bodily injury. To prevent possible injury, follow the established assembly procedure and wear protective equipment.

46. Install the following items into the control valve: backup ring (25), O-ring seal (26), poppet (24), spring (27), O-ring seal (28) and cap (29) .

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Illustration 20	g01223535

47. Install O-ring seal (23) onto adjuster (22). Install adjuster (22) into boom swing control valve (9) .

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Illustration 21	g01223514

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Improper assembly of parts that are spring loaded can cause bodily injury. To prevent possible injury, follow the established assembly procedure and wear protective equipment.

48. Install spool (15) into the control valve.

49. Install the following items into the control valve: washer (16), spring (17) and spring retainer (18).

50. Install O-ring seal (19) onto cap (21). position cap (21) onto the control valve and install bolts (20) .

51. Refer to Step 49 and refer to Step 50 for the opposite side.

52. Position boom swing control valve (9) onto the valve bank.

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Illustration 22	g01223498

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Improper assembly of parts that are spring loaded can cause bodily injury. To prevent possible injury, follow the established assembly procedure and wear protective equipment.

53. Install the following items onto the control valve: O-ring seal (14), pistons (13), springs (12), O-ring seal (11) and O-ring seal (10) .

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Illustration 23	g01223489

54. Install the following items onto outlet control valve (3) : fitting (8), fitting (7), fitting (6), pressure switch (5) and fitting (4) .

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Illustration 24	g01223392

55. Position outlet control valve (3) onto the valve bank. Install nuts (2) .

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Illustration 25	g01223390

56. Install tube assembly (1) onto the valve bank.

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