Component Tests and General Diagnostics

Power Steering Pressure Tester:

^ Tools Required:
- J 5176-E Power Steering Gauge
- J 5421-02 Thermometer

The power steering system test is used to identify and isolate hydraulic circuit difficulties. Prior to performing this test, make the following inspections and corrections if necessary.

Inspect
^ Pump reservoir for proper fluid level.
^ Pump belt for proper tension.
^ Pump drive pulley condition.

Important: All tests are made with the engine idling at normal operating temperature.

1. Place a container under the steering gear or pump to catch the fluid when disconnecting or connecting the hoses.
2. With the engine OFF, disconnect the pressure hose at the steering gear or power steering pump and install J 5176-E to both hoses. The gauge must be between the shutoff valve and pump. Open the shutoff valve.
3. Remove the filler cap from the pump reservoir and check the fluid level. Fill the pump reservoir (with power steering fluid) to the full mark on the dipstick.
4. Start the engine. While momentarily holding steering wheel against stop, check the connections at J 5176-E for leakage.
5. Bleed the system.
6. Insert thermometer J 5421-02 in the reservoir filler opening. Move the steering wheel from stop to stop several times until the thermometer indicates that the hydraulic fluid in the reservoir has reached a temperature of 65° C to 77° C (150° F to 170° F).

Important: To prevent scrubbing flat spots on the tires, do not turn the steering wheel more than five times without rolling the vehicle to change the tire-to-floor contact area.

7. Start the engine and check the reservoir's fluid level. Add power steering fluid if required. When the engine is at normal operating temperature, the initial pressure read on the gauge (valve open) should be in the 550-860 kPa (80-125 psi) range. If this pressure exceeds 1380 kPa (200 psi), check the hoses for restrictions and the poppet valve for proper assembly.

NOTICE: Do not leave valve fully closed for more than five seconds, or the pump could be damaged internally.

8. Fully close the gate valve three times. Record the highest pressures attained each time.
^ If the pressures recorded are within 7585-8274 kPa (1100-1200 psi), and the range of readings within 345 kPa (50 psi), the pump is functioning within its specifications.
^ If the pressures recorded are high, but do not repeat within 345 kPa (50 psi), the flow controlling valve is sticking. Remove the valve, clean it and remove any burrs using crocus cloth or a fine hone. If the system contains some dirt, flush it. If it is exceptionally dirty, both the pump and gear must be completely disassembled, cleaned, flushed, and reassembled before further use.
^ If the pressures recorded are constant but more than 690 kPa (100 psi), below 7585 kPa (1100 psi), replace the flow control valve and recheck. If the pressures are still low, replace the rotating group in the pump.
9. If the pump checks within specifications, leave the valve open and turn the steering wheel to both stops. Record the highest pressures and compare with the maximum pump pressure recorded. If this pressure cannot be reached in either (or one) side of the gear, the gear is leaking internally and must be disassembled and repaired.
10. Shut the engine OFF, remove the testing gauge, reconnect the pressure hose, check the fluid level and/or make the needed repairs.
11. If the problem still exists, the steering and front suspension must be thoroughly examined.