WIRE AS 3778044 - Caterpillar

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 and hydraulic lines or components are disconnected or removed.
3. Release the pressure in the hydraulic system as follows:a. Shut off the engine.b. Move the control levers through their full travel strokes. This will relieve any pressure that may be present in the pilot system.c. Slowly loosen the air breather cap on the hydraulic oil tank to release the pressure.d. Tighten the air breather cap on the hydraulic oil tank.e. The pressure in the hydraulic system has now been released. Lines and components can now be removed. Put identification on all tubes, lines, wires and hoses for installation purposes. Cap all lines to prevent loss of hydraulic oil. 4. Remove four nuts and washers (1).5. Remove cover plate (2). 6. Remove all tube assemblies (4).7. Remove all lines (3).8. Remove three bolts (5) and remove hydraulic control valve (6). The weight of the hydraulic control valve is 20.4 kg (45 lb). Install hydraulic control valve in the reverse order of removal.9. Separate the steering frame lock link. See "Separate & Connect Steering Frame Lock Link" in this module.Disassemble Hydraulic Control Valve-938F & IT38F
Start By:a. remove control valve1. Thoroughly clean the outside of the control valve before disassembly.2. Mark for identification all components for assembly purposes. 3. Remove twelve bolts (2) and washers.4. Remove six spool caps (3) from valve body (1). 5. Six spool caps (3) upon removal.6. Check six O-ring seals (5) for damage or wear and replace if necessary.7. Remove shims (4) from the six spool caps (3). 8. If necessary, remove plugs (6) from spool caps (3).9. Check O-ring seals (7) for wear and replace if necessary. 10. Remove twelve springs (8) from valve body (1) (two springs per bore). 11. Remove six springs (9). 12. Remove three valve spools (10). 13. Remove four relief valves (11). 14. Remove relief valve (12). Relief valve (12) has two O-ring seals. Check for damage or wear and replace if necessary. 15. Remove plug (13). 16. Remove spring (14) and check valve (15). Check valve (15) has one O-ring seal and one back-up ring check for damage or wear and replace if necessary. 17. If necessary, remove remaining ten plugs (16) and their seals. There are seven plugs on this side, and three on the back.Assemble Hydraulic Control Valve-938F & IT38F
1. If removed, install ten plugs (16) and their seals. There are seven plugs on this side, and three on the back. 2. Install spring (14) and check valve (15). Check valve (15) has one O-ring seal and one back-up ring check for damage or wear and replace if necessary. 3. Install plug (13). 4. Install relief valve (12). Relief valve (12) has two O-ring seals. Check for damage or wear and replace if necessary. Torque for nut on main relief valve nut 50 7 N m (37