Usage:
Fluid Spillage Containment
Care must be taken to ensure that the fluids are contained during performance of the inspection, the maintenance, the testing, the adjusting and the repair of the machine. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids. Refer to the "Tools And Shop Products Guide, NENG2500" the tools and the supplies suitable to collect and contain any of the fluids in Caterpillar machines. Dispose of the fluids according to local regulations and mandates.
NOTE: The removal and the installation procedure for both of the pilot control valves (implement) is the same. The procedure which follows shows the removal and the installation of the pilot control valve for the swing and the stick control functions.
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At operating temperature, the hydraulic oil tank is hot and under pressure. Hot oil can cause burns. To prevent possible personal injury, release the pressure in the hydraulic system before any of the hydraulic lines or any of the components are disconnected or removed. |
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1. Release the pressure in all of the implement hydraulic circuits (the boom, the stick and the bucket) before any of the hydraulic lines or any of the components are disconnected or removed, as follows:
a. Fully retract the stick cylinder rod.
b. Adjust the position of the bucket so that it will be flat on the ground when the boom is lowered.
c. Lower the boom until the bucket is flat on the ground.
d. Shut off the engine and place key in the "ON" position. Put the hydraulic activation control lever in the "UNLOCK" position.
e. Move the control levers for the boom, the stick and the swing to all full stroke positions. This will release any pressure that might be present in the pilot system.
f. Return the key to "OFF" position.
g. Slowly loosen the fill plug on the hydraulic tank and release the pressure.
h. Tighten the fill plug on the hydraulic tank. Tighten the fill plug to a torque of 68 ± 7 N*m (50 ± 5 lb ft).
i. The pressure in the hydraulic system has been released and the hydraulic lines and the components can be removed.
2. Remove cover (1) from the left console. Remove the two screws located under the cover.
3. Remove two screws (2) and side cover (3) from the left console.
4. Remove cover (4) from the left console.
5. Remove seven screws (5). Place fuse set holder (6) in the arm rest of the left console.
6. Lift top cover (10) off of the left console. Put identification marks on electrical connectors (11) for installation purposes. Disconnect electrical connectors (11).
7. Remove rubber boot (7).
NOTE: If the implement pilot control valve is to be disassembled and assembled, the control lever assembly can be removed from the valve at this time.
8. In order to maintain the correct height of cam (9) from the valve stems in implement pilot control valve, do not loosen nut (8) from cam (9). Remove cam (9) and the control lever assembly as a unit.
9. Remove the two screws that hold switch assembly (12) in position.
10. Remove plate (13) from the implement pilot control valve.
11. Remove three bolts (14) that hold the implement pilot control valve in the console.
12. Put identification marks on six hose assemblies (16) that are connected to the implement control valve for installation purposes.
13. Oil will drain from six hose assemblies (16) when they are disconnected from the implement pilot control valve. Place a drain pan under the implement pilot control valve to contain the drain oil. Raise implement pilot control valve (15) out of the console. Disconnect six hose assemblies (16) from the valve. Put plugs in the ends of the hose assemblies to prevent oil loss and to keep contaminants out of the hydraulic system. Remove implement pilot control valve (15) from the machine.
NOTE: The following steps are for the installation of the implement pilot control valves.
14. Check the condition of all O-ring seals used in the ends of six hose assemblies (16). If the seals are damaged, use new parts for replacement.
15. Install implement pilot control valve (15) in the reverse order of removal. Tighten six hose assemblies (16) to a torque of 40 ± 5 N*m (30 ± 4 lb ft).
NOTE: Refer to the topic "Lubricant Viscosities and Refill Capacities" in the "Operation & Maintenance Manual" for the proper filling procedure and the proper levels for the hydraulic oil system.
16. Check the oil level in the hydraulic oil tank. Fill the hydraulic oil tank with oil to the correct level.
Disassemble & Assemble Pilot Control Valves (Swing & Stick Control/Bucket & Boom Control)
Start By:
a. remove pilot control valve (swing and stick control)
b. remove pilot control valve (bucket and boom control)
NOTE: The disassembly and the assembly procedure for both of the pilot control valves (implement) is the same.
1. Make sure the out side of the implement pilot control valve is thoroughly clean prior to disassembly. Put identification marks on all parts of the implement pilot control valve for assembly purposes.
2. Remove six fitting (1) from the bottom side of the implement pilot control valve.
3. Remove two socket head bolts (2), the washers and bottom plate (3).
4. Remove O-ring seal (4) from the valve body assembly.
5. Use Tool (A) or (B) to measure the distance from the top of nut (5) to the top surface of universal joint (6). Record this dimension.
6. Place the implement pilot control valve in a soft jawed vise as shown.
7. Tighten cam (7) against nut (5). Using a suitable size open end wrench, loosen cam (7) so it, universal joint (6) and nut (5) are removed as a unit. Remove nut (5) and cam (7) from universal joint (6).
8. Remove plate (8).
9. Remove rod (9) and plug (10) from the valve body. Remove external O-ring seal (12) and internal lip seal (14) from plug (10).
10. Remove spring (11) and pin (13) from rod (9).
Exploded View Of Complete Valve Assembly.
11. Remove valve assembly (15) and spring (16) from the valve body.
12. Disassemble valve assembly (15) as follows:
a. Compress seat (18) by hand, and remove retainer plates (21).
b. Remove seat (18), spring (20), washers (17) and spool (19).
13. Remove the other three valve assemblies from the valve body as in Steps 9 through 12.
NOTE: The following steps are for the assembly of the implement pilot control valve.
14. Make sure all parts of the implement hydraulic control valve are thoroughly clean. Check the condition of all parts of the implement hydraulic control valve. If any of the parts are worn or damaged, use new parts for replacement. Apply clean hydraulic oil on all parts of the implement hydraulic control valve during assembly.
Exploded View Of Complete Valve Assembly
15. Assemble valve assembly (15) as follows:
a. Install two washers (17) and spring (20) on spool (19). Install the spool in seat (18).
b. Compress seat (18) by hand, and install two retainer plates (21).
16. Install spring (16) and valve assembly (15) in the valve body.
17. Install lip seal (14) and O-ring seal (12) on plug (10).
18. Install pin (13) and spring (11) in rod (9).
19. Install rod (9) and plug (10) in the valve body.
20. Assemble and install the other three valve assemblies in the valve body as in Steps 15 through 19.
21. Install plate (8).
22. Install universal joint (6), and tighten it to a torque of 47 ± 3 N*m (35 ± 2 lb ft).
23. Install cam (7) and nut (5). Locate the nut on the joint to the dimension that was recorded in Step 5.
24. While holding cam (7) in position, tighten nut (5) against the cam to a torque of 69 ± 5 N*m (50 ± 4 lb ft).
25. Use Tool (A) and (B) to check the dimension between the top of nut (5) and the top surface of universal joint (6). The dimension must be the same as recorded in Step 5. If the dimension is different, repeat Step (24).
26. Install O-ring seal (4) in the valve body assembly.
27. Put bottom plate (3) in position on the valve body assembly. Install two socket head bolts (2). Tighten the bolts to a torque of 29 ± 3 N*m (21 ± 2 lb ft).
28. Install an O-ring seal on each fitting (1). Install six fittings (1) in the bottom plate. Tighten each fitting to a torque of 40 ± 5 N*m (30 ± 4 lb ft).
End By:
a. install pilot control valve (bucket and boom control)
b. install pilot control valve (swing and stick control)