CYLINDER GP-BOOM 3747248 - Caterpillar

Personal injury or death can result from sudden machine movement.Sudden movement of the machine or release of oil under pressure can cause injury to persons on or near the machine.To help prevent possible injury, perform the procedure that follows before testing and adjusting the hydraulic and steering system:
This test is used primarily in order to identify problems in the steering hydraulic circuit. The test can identify some problems in the circuit for an implement.Tools Needed 1U-5796 Gauge for Pressure Differential 9U-7400 Multitach
Move the machine to a clear area that is level. Lower the implements to the ground. Stop the engine.
Illustration 1 g00501669
Implement hydraulic pump (1) Tap for the pump discharge pressure (2) Pressure tap for the signal oil
Remove the floorplates. Install two 1U-5755 Hose Assemblies on pressure taps (1) and (2) .
Connect the other ends of the hoses to the 1U-5793 Gauge for Pressure Differential. Connect the hose from pressure tap (1) to the tee side of the gauge. Connect the hose from pressure tap (2) to the elbow side of the gauge.
Install a 60000 kPa (8700 psi) pressure gauge on the tee side of the gauge.
Make sure that the steering linkage is correctly adjusted. Refer to the test for low pressure standby in Testing and Adjusting, "Pump Discharge Pressure - Test".
Install the floorplates.
Install 9U-7400 Multitach on the tach drive location of the engine.
Start the engine and run the engine at high idle. Record the rpm, which should be 2254 30 rpm for the standard machine and 2245 30 rpm for the LGP machine. Refer to the Engine Information Plate or to the Fuel Settings and Related Information Microfiche.
When the engine is still at high idle, move the bulldozer control lever to a midway position between the HOLD and FULL RAISE positions. While the bulldozer blade is being raised, read the pressure differential. Record the reading. The reading on the gauge is called the margin pressure. This pressure differential is the difference between the pump discharge pressure and the signal pressure from the control valve. The margin pressure should be 2100 275 kPa (305 40 psi). If the margin pressure is not correct, refer to Testing and Adjusting, "Pressure and Flow Compensator Valve (Steering) - Adjust" for adjustment of the margin pressure and the pressure and flow compensator valve. When the margin pressure is adjusted, the setting should be in the range of 2100 70 kPa (305 10 psi).
Lower the bulldozer blade to the ground. Move all implement control levers to the HOLD position.
Release the parking brakes. Fully activate the service brakes. The transmission speed control must be in the NEUTRAL position. The transmission direction control handle must be in the NEUTRAL position.
Keep the engine running at high idle. Move the tiller handle to the MID STEER RIGHT POSITION. The hydraulic system is now in a steer stall condition.Note: The machine must not move. If the machine moves, the brake system must be checked.
With the machine in a steer stall condition, record the