Component Tests and General Diagnostics
HYDRAULIC FLOW AND PRESSURE TEST
Special Tools:
WARNING: To prevent personal injury, safety goggles should be worn at all times while performing any test procedures on the power steering system.
The following procedure is to be used to test the operation of the power steering system on this vehicle. This test will provide the flow rate (Gallons Per Minute (GPM)) of the power steering pump along with the maximum relief pressure. Perform this test any time a power steering system problem is present. This test will help determine if the power steering pump or power steering gear is not functioning properly. The test is performed using tools in the Power Steering Analyzer Kit with appropriate hoses and adapters. Tools and Equipment
1. Check the power steering belt to ensure it is in good condition and adjusted properly.
2. Assemble the following hoses and adapters on the Flow Meter And Gauge (3):
a. Gauge end (inlet) - Hose (6) (in kit), Hose (4) (in kit), Adapter Tube (5) (in kit)
b. Valve end (outlet) - Hose (1), Adapter Fitting (2)
NOTE: In the following steps, figures showing the four-cylinder gas engine have been used. Pump location differs depending on engine application, but a standard pressure hose tube nut fitting is used by all.
3. Unthread the tube nut (3) and disconnect the power steering pressure hose (1) at the power steering pump pressure fitting (5).
4. Connect the vehicle's power steering pressure hose (2) to Adapter Fitting (5) (on Hose (1) leading to Analyzer outlet). Tighten the tube nut. [1][2]Specifications
5. Connect Adapter Fitting (4) (on Hose (3) leading to Analyzer inlet), to the open power steering pump pressure fitting (6). Tighten the tube nut. [1][2]Specifications
6. Route the hoses away from the exhaust system as well as possible.
TEST PROCEDURE
1. Completely open the valve on the Power Steering Analyzer flow meter.
2. Start the engine and let idle long enough to circulate power steering fluid through the analyzer and hoses, until the air is out of the fluid. Shut off the engine.
3. Check the power steering fluid level and add fluid as necessary. Start the engine again and let idle.
4. The analyzer gauge should read below 862 kPa (125 psi). If above, inspect the hoses for restrictions and repair as necessary. The pressure once the engine is warm should be in the range of 345-552 kPa (50-80 psi). The flow meter should read above 1.5 GPM.
CAUTION: The following test procedure step involves testing maximum pump pressure output and flow control valve operation. Do not leave valve closed for more than five seconds as the pump could be damaged.
NOTE: Power steering pump maximum relief pressure is 10,500 to 11,900 kPa (1525 to 1725 psi).
5. Close the flow meter valve fully three times and record highest pressure indicated each time. All three readings must be within specifications and within 690 kPa (100 psi) of each other.
- If the power steering pump pressures are within specifications, but not within 690 kPa (100 psi) of each other, replace the power steering pump.
- If the pressures are within 690 kPa (100 psi) of each other, but are outside of specifications, replace the power steering pump.
If the power steering pump requires replacement, Power Steering Pump - Removal.
CAUTION: During the next step, do not force the pump to operate against the stops for more than 5 seconds at a time as pump damage may result.
6. Completely open the valve on the Power Steering Analyzer flow meter. Turn the steering wheel to the extreme left until the stop in the steering gear is met, then turn the steering wheel to the right until the right stop is met. Record the highest indicated pressure at each position. Compare the recorded readings to the specifications. If the highest output pressure reading against one stop is not within 690 kPa (100 psi) of the highest reading at the other stop, the steering gear is leaking internally and must be replaced.
If the power steering gear requires replacement, Steering Gear - Removal.