TUBE AS 9V8990 - Caterpillar

At operating temperature, the hydraulic oil tank is hot and under pressure. Hot oil can cause burns. Remove the breather filter cap only when the engine is stopped and the breather filter cap is cool enough to touch. Slowly loosen the breather filter cap to release any pressure in the hydraulic tank. Be cautious of hot hydraulic oil when any lines are disconnected in the hydraulic system.
Put identification on all lines, hoses, wires and tubes for installation purposes. Cap and plug all lines, hoses and tubes to prevent foreign material from entering the system. Drain all fluids in a suitable container for storage or disposal. 1. Disconnect two hose assemblies (1).2. Remove mounting bolt (2).3. Remove valve group (3). Install in the reverse order. Refer to the Operation & Maintenance Manual for all fluid capacities and the proper filling procedures.Disassemble & Assemble Tailgate Cylinder Valve
Start By:a. remove tailgate cylinder valve 1. Remove mounting bolt (1) and seal (3) from valve group (2).2. Remove elbow (5), O-ring (8), and O-ring (4).3. Remove elbow (12) and O-ring (11).4. Remove elbow (6), O-ring (9), and O-ring (7).5. Remove valve cartridge (13) and O-ring (10). The valve cartridge is not serviceable. Before installation, check the O-rings or seals for wear or damage. Replace as required.For assembly of the tailgate cylinder valve, reverse the disassemble steps.End By:a. install tailgate cylinder valve