REGULATOR AS 5N5081 - Caterpillar

Instrument testing on the hydraulic system and its components is the final step when diagnosing a problem. Test results should verify the status of a component. Adjusting procedures are provided where needed.Pressure Tap Location
(1) Pressure tap location.Pump Discharge Pressure Tests
Pump discharge pressures are known values and can be tested during two specific conditions. These two conditions are low pressure standby and high pressure stall.Low Pressure Standby Test Procedure
1. Lower the bucket to the ground.2. Stop the engine and move the steering wheel to all positions to release system pressure.3. Relieve the tank pressure by opening the fill cap slowly.4. Remove the plug and install a 0 to 6000 kPa (0 to 870 psi) gauge in pump pressure tap location (1).5. Start the engine and run at high idle rpm.6. Leave steering in HOLD.7. The pressure reading must be 4300 kPa (624 psi) maximum. Margin pressure is 2800 kPa (406 psi). Low pressure standby pressure is approximately an additional 1500 kPa (218 psi) higher than margin pressure. Low pressure standby could be as low as 3100 kPa (450 psi).8. Adjustments to pump output should not be made based only on the results of this test. Instead, if the results are not acceptable, the Margin Pressure Test should also be run.High Pressure Stall Test Procedure
5S5123, 5P5224 or 6V4161 Pressure Gauge Kit.1. Lower the bucket to the ground.2. Stop the engine and move the steering wheel to all positions to release system pressure.3. Relieve the tank pressure by opening the fill cap slowly.4. Install a 0 to 28 000 kPa (0 to 4060 psi) gauge at pump pressure tap location (1).5. Start the engine and run at high idle rpm.6. Move steering wheel all the way to the left to the stop, initiating a stall condition. Move the steering wheel all the way to the right to the stop, initiating a stall condition. Record the pressures while in the stall condition.7. The Maximum System Pressure reading must be 20 700 350 kPa (3000 50 psi). If the pressure readings are all too low or too high, the pressure compensator valve needs to be adjusted. See Compensator Valve Adjustment.Margin Pressure Test
1U5796 Differential Pressure Group7X2444 Swivel Tee (1 each)6V3965 Nipple (1 each)3J1907 Seal (1 each)1. Lower the bucket to the ground.2. Stop the engine and turn the steering wheel all the way to the left and then all the way to the right to release system pressure.3. Relieve the tank pressure by opening the fill cap slowly.4. Remove side cover from the left side of machine.5. Disconnect the signal line at the compensator valve and install a 7X2444 Swivel Tee with a 6V3965 Quick Disconnect Nipple.6. Connect differential pressure gage group to pump pressure tap (1) and to the 6V3965 Quick Disconnect Nipple installed in Step 5.7. Start the engine and run at low idle rpm. Check for leaks.8. Warm up the hydraulic oil. Check for leaks.9. Raise the engine to high idle rpm.10. Move the steering wheel to either a