HEATER AS-SCREED 3501489 - Caterpillar

Disassembly Procedure
Start By:
Remove the pilot valve. Refer to Disassembly and Assembly, "Pilot Valve (Joystick) - Remove". Note: Cleanliness is an important factor. Before the disassembly procedure, the exterior of the component should be thoroughly cleaned. This will prevent dirt from entering the internal mechanism.
Illustration 1 g00741704
Spool assembly (17) is installed in port (1) and port (3) in the pilot valve.
Spool assembly (18) is installed in port (2) and port (4) in the pilot valve.
Spring seat (7) is installed in port (1) and port (3) in the pilot valve.
Spring seat (10) is installed in port (2) and port (4) in the pilot valve.
Illustration 2 g00914163
Remove rubber boot (4) from the pilot valve.
Illustration 3 g01021450
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.
Measure Distance (A) from the top of plate (12) to the top of plate (20). Record Dimension (a) for assembly purposes.
Tighten nut (8) against plate (12). Remove plate (12), nut (8), and U-joint (14). Note: If U-joint (14) or plate (12) is not being replaced, do not remove plate (12) from U-joint (14).
Remove nut (8) from U-joint (14).
Remove plate (12) from U-joint (14).
Remove plate (20) from the pilot valve.
Illustration 4 g00914179Note: The spring seat and the spring may fall out of the rod while you remove the plug.Note: Mark the seat and the spring for assembly purposes. Spring seat (7) is installed in port (1) and port (3) in the pilot valve. Spring seat (10) is installed in port (2) and port (4) in the pilot valve.
Remove plug (2) from the pilot valve.
Remove spring seat (7) or (10) and spring (6) from rod (5).
Remove rod (5) from plug (2).
Remove O-ring seal (3) from plug (2).
Remove seal (1) from plug (2). Note: Spool assembly (17) is installed in Port (1) and Port (3) in the pilot valve. Spool assembly (18) is installed in Port (2) and Port (4) in the pilot valve.
Remove the spool assembly from the pilot valve.
Use the following procedure to disassemble the spool assembly. Note: Spool (22) is assembled in Port (1) and Port (3) in the pilot valve. Spool (23) is assembled in Port (2) and Port (4) in the pilot valve.
Apply pressure to seat (11) by hand. Put the end of the spool in the slotted opening of seat (11). Remove seat (11). Note: Spring (13) is installed on spool (22). Spring (15) is installed on spool (23).
Remove spring (13) or spring (15) from the spool.
Remove washer (19) from the spool.
Remove spring (26) from the pilot valve.
Repeat Steps 7 through 14 in order to remove the other three spool assemblies.
Illustration 5 g00914124
Remove bolts (28) and washers (27).
Remove plate (25) from the pilot valve.
Remove spring pin (24) from plate (25).
Remove O-ring seal (21) from valve body (9).
Remove bushing (16) from valve body (9).