PULLEY-CRANKSHAFT 4W8508 - Caterpillar

2. Disconnect the hydraulic lines from control valve (1).3. Attach a hoist. Remove the mounting bolts holding valve (1) to the machine frame. Remove control valve (1). Control valve (1) weighs approximately 85 kg (187 lb).4. Install control valve (1) in the reverse order of removal.5. Fill the hydraulic tank with oil to the correct level. See the Operation & Maintenance Manual.Disassemble & Assemble Hydraulic Control Valve
Start By:a. remove hydraulic control valve 1. Remove four bolts and washers (7). Remove four bolts (4). Remove counterbalance valve group (5) from valve group (9).2. Remove six bolts (1) and one relief valve group (3) from valve group (9).3. Remove six bolts (1) and the other relief valve group (3) from valve group (9).4. Remove seal (2) and two O-ring seals (8) from each relief valve group (3). Remove the plugs. 5. Disassemble each relief valve group (3) as follows:
The bolts and plugs in the following steps are under spring force. Remove them slowly to release the spring force.
a. Remove stop assembly (10) and O-ring seal (9).b. Remove plug assembly (12). If necessary, remove the sleeve bearing and the O-ring plug.c. Remove spring (11) and valve (13).d. Remove three bolts (18) and cover (22). Remove O-ring seal (21).e. Remove plug (20) and the O-ring seal.f. Remove four shims (17) and five spacers (19).g. Remove spring (16).h. Remove valve (24) from pilot seat (23). At assembly valve (24) must be lapped to pilot seat (23) for the relief valve to function properly.j. Remove seal (25) from pilot seat (23).k. Remove springs (14) and (15). l. Remove valve (26) from relief valve group (3).m. Assemble each relief valve group (3) by reversing Steps L through A. 6. Disassemble counterbalance relief valve (5) as follows:a. Remove plugs (32) and (33).
Bolt (34) holds two retainers with springs under tension. Remove slowly to release the spring force.
b. Remove bolt (34).c. Remove retainer (27).d. Remove spring (29).e. Remove retainer (38) and spring (28) from housing (30).f. Remove retainer (37) and two hard washers (36).g. Remove spacer (35).h. If necessary, remove bleeder screw (31).j. Assemble the counterbalance relief valve by reversing Steps H through A.7. Assemble counterbalance relief valve (5) to valve group (9) with four bolts (7) and four bolts (4).8. Assemble two O-ring seals (8) and one seal (2) to each relief valve group (3). Install each valve group (3) with six bolts (1).End By:a. install hydraulic control valve