HOSE-RADIATOR 3775176 - 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 implement hydraulic circuits (boom, stick and bucket) before any hydraulic lines or components are disconnected or removed.
1. Release the pressure in the hydraulic system as follows: a. Fully retract the rod in the stick cylinder.b. Adjust the position of the bucket so 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 put the hydraulic activation control lever in the "Lock" position.e. Move the control levers for the boom, bucket, stick and swing through their full travel strokes. This will relieve any pressure that may be present in the pilot system.f. Slowly loosen the air breather cap on the hydraulic oil tank to release the pressure.g. Tighten the air breather cap on the hydraulic oil tank.h. The pressure in the hydraulic system has now been released. Lines and components can now be removed.
View From Under Cab2. Remove bolts (1), the washers and spacers that hold access cover (2) in place. Remove the access cover from under the cab. 3. Disconnect rod (7) from the hydraulic activation control valve.4. Put identification marks on eleven hose assemblies (6) that are connected to the hydraulic activation control valve so they can be reinstalled in their original location. Disconnect the eleven hose assemblies from the hydraulic activation control valve. Put plugs in the ends of the hose assemblies to prevent oil loss and to keep dirt and debris out of the hydraulic system.5. Disconnect wiring harness (3) from the switch assembly in the hydraulic activation control valve.6. Remove two bolts (4) and the washers that hold the hydraulic activation control valve in place. Remove hydraulic activation control valve (5). The following steps are for the installation of the hydraulic activation control valve.7. Put hydraulic activation control valve (5) in place under the cab. Install the two washers and bolts (4) that hold it.8. Connect rod (7) to the hydraulic activation control valve.9. Connect wiring harness (3) to the switch assembly in the hydraulic activation control valve.10. Check the condition of the O-ring seals used in the ends of the hose assemblies that are connected to the hydraulic activation control valve. If any of the seals are damaged, use new parts for replacement.11. Connect eleven hose assemblies (6) to the hydraulic activation control valve in their original locations.12. Reinstall access cover (2) under the cab.13. Check the oil level in the hydraulic oil tank. Fill the hydraulic oil tank with oil to the correct level. Refer to the 350 & 350 L Excavators Operation & Maintenance Manual for the correct filling procedure.Disassemble & Assemble Hydraulic Activation Control Valve
Start By:a. remove hydraulic activation control valve1. Make sure the hydraulic activation control valve is thoroughly clean prior to disassembly. 2. Put identification marks on all hydraulic fittings in the valve