Service Manual User Manual

Hydraulic System
9-71
Main Control Valve Assembly Legend
(with auxiliary hydraulics)
1. Auxiliary Control Valve
2. Auxiliary Control Valve Mounting Bracket
3. Lockwasher, 3/8"
4. Hex-head Capscrew, 3/8-16 x 1-1/4"
5. Hex-head Capscrew, 3/8-16 x 3/4" Gr. 5
6. Hose, 1/2" ID x 21"
7. Hose, 1/2" ID x 26"
8. Hose, 3/8" ID x 21-1/2"
9. Hose, 3/8" ID x 10-1/2"
10. Hose, 3/8" ID x 26"
11. Hose, 3/8" ID x 41"
12. Modified 90° Elbow, SAE 6,
Str. Thd. ORB x O-Ring Face Seal
13. 90° Elbow, SAE 6 - Str. Thd. ORB x O-Ring Face Seal
14. Swivel Run Tee, SAE 8 - O-Ring Face Seal
15. Swivel Run Tee, SAE 6 - O-Ring Face Seal
c. Main Control Valve Disassembly
The main control valve (Fig. 9– 53 and Fig. 9– 54) consists
of various section assemblies held together by three tie
rods (items 4 and 5, Fig. 9– 54), secured with special hex
nuts (2 and 3). From left to right, the section assemblies
are the attachment and frame tilt outlet section assembly,
attachment tilt section assembly, frame tilt section
assembly, mid inlet section assembly, boom extend/
retract section assembly, boom hoist/lower section
assembly, and the extend/retract and hoist/lower outlet
section assembly. Each section assembly includes a pre-
adjusted relief valve assembly that regulates pressure in
a specific circuit.
IMPORTANT: DO NOT adjust any of the relief valve
assemblies! Tampering with a relief valve assembly will
irrevocably alter pressure in the affected circuit, requiring
re-calibration or a new relief valve assembly.
16. Connector, SAE 6 - Str. Thd. ORB x O-Ring Face Seal
17. 90° Swivel Elbow, SAE 6 - O-Ring Face Seal
18. Cap, SAE 6 - O-Ring Face Seal
19. Connector, SAE 8-10 - Str. Thd. ORB x O-Ring Face Seal
20. Union Connector, SAE 6-4,
O-Ring Face Seal x O-Ring Face Seal
21. Solenoid Valve (service with Kit, Item 29)
22. Coil w/Female Pins
23. Diagnostic Nipple
24. Dust Plug
25. Manually Operated Relief Valve
26. Plain Washer, 1/4"
27. Lockwasher, 1/4"
28. Hex-head Capscrew, 1/4-20 x 2"
29. Kit, Valve Seal
To disassemble the main control valve:
1. Place the valve plate assembly on a suitable work
surface.
2. Working from beneath the main valve bracket (5,
Fig. 9– 51), remove the hex-head capscrews (32 and
33), lockwashers (30) and plain washers (28)
securing the main control valve (2) to the bracket (5).
Remove the main control valve from the bracket.
3. Disassemble the main control valve by removing the
special nuts (2 and 3, Fig. 9– 54) from one end of the
tie rods (4 and 5). Pull the tie rods out through the
section assemblies.
4. Disassemble each section assembly as required.
Model 3606 • Origin 10/99