Testing the Pressure on Your Imperial's Power Steering Pump

Imperial Homepage -> Repair  -> Steering -> Power Steering Pump -> Pressure Test

1)  Start the engine, turn the steering wheel all the way to the left and back all the way to the right several times to expel air fromt he system, then shut off the engine.


2)  Remove the filler cap and visually check the oil level of the pump's reservoirs.  Fill if necessary with power steering fluid so reservoirs are full.

Engine cold -- Oil level should be at the bottom of the filler neck.

Engine hot -- Oil level should be one-half way up the filler neck.

3)  Check the pump belt tension.


4)  Disconnect the pump to the steering gear pressure hose at the power steering pump.  Connect a hydraulic pressure gauge (tester that you can purchased at any auto parts store) which will allow you to test the pressure.  Make sure all the connections are tight and that the shut-off valve is fully opened.


5)  Start the engine and operate at idle speed.


6)  With the engine operating at idle and oil temperature between 150 degrees F and 170 degrees F, the pressure gauge should show a pressure of 55 to 80 psi.  If the pressure is higher, check the hoses and connections for kinks and obstructions, check the pump or flow control valve for faulty operation.


7)  Increase the engine speed to 1000rpm, then slowly close the gauge shut-off valve.  The pump pressure should be 950 to 1150 psi with the gauge shut-off valve fully closed.


Do not close the valve for more than a few seconds, as this would abnormally increase the oil temperature and cause undue oil pump wear.


a.  If the pressure increases more than 1050 psi, the relief valve is faulty or the pump is equipped with the wrong relief valve.

b.  If the pressure is less than 950 psi, the pump is faulty.

c.  If the pressure is within the specified range of 950 to 1050 psi, the pump is operating properly and the trouble is in the steering gear.

d.  Open the gauge shut-off valve and operate the steering unit through another cycle, the time holding unit at extreme travel in each direction while watching the oil pressure gauge.  The gauge reading should be equal in each direction.  If not, it indicates excessive internal leakage in the unit.  Do not hold the wormshaft at either extreme position for more than a few seconds.

This page last updated September 28, 2001.  Send us your feedback, and come join the Imperial Mailing List - Online Car Club