COVER AS 1569329 - Caterpillar

Sudden movement of the machine or release of oil under pressure can cause injury to persons on or near the machine.To prevent possible injury, perform the procedure that follows before testing and adjusting the brake system.
Escaping fluid under pressure, even a pinhole size leak, can penetrate body tissue, causing serious injury, and possible death. If fluid is injected into your skin, it must be treated immediately by a doctor familiar with this type of injury.Always use a board or cardboard when checking for a leak.
General Information
The Testing and Adjusting, "Hydraulic Pump - Test and Adjust" should be completed before performing this test. This will ensure that the flow compensator, the pressure compensator and the torque limiter are set correctly.
Table 1
REQUIRED TOOLS    
Part Number     Description     Quantity    
177-7860     Hose Assembly     1    
6V-4143     Coupler     2    
8T-0860     Pressure Gauge     1    
Illustration 1 g01072492
(1) Hydraulic pump (2) Signal pressure tapThe signal pressure tap (2) is located on the hydraulic pump (1). Access is gained from the bottom of the machine or access is gained by removing the floorplate.
Illustration 2 g01050788
(3) Relief valve (4) Locknut (5) Adjusting screwThe priority valve is part of the inlet manifold on the bank valve for the loader control. Access to the bank valve for the loader control is from the bottom of the machine. The relief valve (3) is located on the priority valve.The relief valve limits the signal pressure to the pump. The relief valve drains the signal pressure to the tank when the pressure rises above the relief valve setting.Test for Relief Valve
Install one 6V-4143 Coupler to each end of each the 177-7860 Hose Assembly .
Install one 8T-0860 Pressure Gauge with a range of 0 to 40,000 kPa (0 to 5800 psi) to the hose. Install the hose to signal pressure tap (2) .
Engage the parking brake. Start the engine. Keep the machine in NEUTRAL.
Run the engine at HIGH idle.
Turn the steering wheel in both directions until the relief valve opens. Note the indication on the gauge. The correct pressure setting for the relief valve is 17250 345 kPa (2500 50 psi).Note: There may be air in the signal network, if there is a hesitation before reaching the relief pressure. Purge the signal lines of the air.Note: The inlet check valve for the metering pump prevents steering kickback. Steering kickback requires replacing the inlet check valve.
If the pressure for the relief valve is correct, then go to Step 12. If the relief pressure is not correct, then the relief valve needs adjusting.
Stop the engine.
Loosen locknut (4) on steering relief valve (3) .
Turn the adjusting screw (5) clockwise in order to increase the pressure. Turn the adjusting screw (5) counterclockwise in order to decrease the pressure.
Tighten locknut (4) .
Repeat Steps 4, 5, and 6. If the relief valve can not be set correctly, replace the priority valve.
Turn off the engine and remove the test equipment.