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Flow And Pressure Test

  1. Check the power steering belt to ensure it is in good condition and adjusted properly.
  2. Connect pressure gauge hose from the Power Steering Analyzer to Tube (special tool #6825A, Adapter, Power Steering).
  3. Connect Adapter (special tool #6826, Adapter, LH P/S Tester) to Power Steering Analyzer test valve end.
  4. Disconnect the high pressure hose from the power steering pump.
  5. Connect the tube to the pump hose fitting.
  6. Connect the power steering hose from the steering gear to the adapter.
  7. Open the test valve completely.
  8. Start engine and let idle long enough to circulate power steering fluid through flow/pressure test gauge and to get air out of the fluid. Then shut off engine.
  9. Check fluid level, add fluid as necessary. Start engine again and let idle.
  10. Gauge should read below 862 kPa (125 psi), if above, inspect the hoses for restrictions and repair as necessary. The initial pressure reading should be in the range of 517-689 kPa (75-100 psi).
    CAUTION:

    The following test procedure involves testing maximum pump pressure output and flow control valve operation. Do not leave the valve closed for more than three seconds as the pump could be damaged.

  11. Increase the engine speed to 1500 RPM and read the flow meter. If the flow rate (GPM) is below specification, the pump should be replaced. Refer to PUMP SPECIFICATION 
  12. Close valve fully three times and record highest pressure indicated each time. All three readings must be above specifications and within 345 kPa (50 psi) of each other. 
    • Pressures above specifications but not within 345 kPa (50 psi) of each other, replace pump.
    • Pressures within 345 kPa (50 psi) of each other but below specifications, replace pump.
    CAUTION:

    Do not force the pump to operate against the stops for more than 2 to 3 seconds at a time because, pump damage will result.

  13. Open the test valve and turn the steering wheel to the extreme left and right positions three times against the stops. Record the highest pressure reading at each position. Compare readings to the pump specifications chart. If pressures readings are not within 50 psi of each other, the gear is leaking internally and must be replaced.
PUMP SPECIFICATION

SYSTEM RELIEF PRESSURE ± 50 FLOW RATE (GPM) AT 1500 RPM
WITHOUT EHPS 11721 kPa (1700 psi) 2.5 - 3.0 GPM
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