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Hydraulic Pressure

NOTE:
  • To measure hydraulic pressure correctly, be sure to complete all the items in "INSPECTION", prior to performing the measurement. Refer to POWER ASSISTED SYSTEM (POWER STEERING)>GENERAL DIAGNOSTIC TABLE>INSPECTION .
  • Do not leave the valve of pressure gauge closed or hold the steering wheel at lock for 5 seconds or more in any case, this can damage the oil pump.
  • Before attaching a pressure gauge, place cloth at locations where fluid is expected to spill. Wipe off any spilt fluid completely after the measurement.
  1. Regular pressure measurement
    1. Connect the ST.

      Preparation tool: 

      ST1: PRESSURE GAUGE (925711000)

      ST2: ADAPTER HOSE B (34099AC020)

      ST3: ADAPTER HOSE A (34099AC010)

    2. Remove the air intake duct. Refer to INTAKE (INDUCTION) (STI)>AIR INTAKE DUCT>REMOVAL .
    3. Disconnect the pressure hose from the pump.
    4. Using the gasket and bolt, install the ST2 to the pump instead of the pressure hose.

      Preparation items: 

      Genuine part: Gasket (34621AC021)

      Genuine part: Bolt (34620AC010)

      G13648485Courtesy of SUBARU OF AMERICA, INC.
    5. Attach the ST3 to the end of pressure hose which is removed from pump.
    6. Replenish power steering fluid up to the specified level.
    7. Open the valve, and start the engine.
    8. Measure the regular pressure.

      Preparation tool: 

      ST1: PRESSURE GAUGE (925711000)

      ST2: ADAPTER HOSE B (34099AC020)

      ST3: ADAPTER HOSE A (34099AC010)

      G13648486Courtesy of SUBARU OF AMERICA, INC.

      Service limit: 

      981 kPa (10 kgf/cm2 , 142 psi) or less

    9. If it is not within the specification, replace the faulty part for the following problems. (Pipe or hose clogged, leaks from fluid line, and mixture of foreign matter in fluid line)
  2. Measure the relief pressure.
    1. Using the ST, measure the relief pressure.
    2. Close the valve.
    3. Measure the relief pressure.

      Preparation tool: 

      ST1: PRESSURE GAUGE (925711000)

      ST2: ADAPTER HOSE B (34099AC020)

      ST3: ADAPTER HOSE A (34099AC010)

      G13648487Courtesy of SUBARU OF AMERICA, INC.

      Service limit: 

      8, 300 - 9, 000 kPa (85 - 92 kgf/cm2 , 1, 203 - 1, 305 psi)

    4. If the torque is not within specified range, replace the oil pump.
  3. Measure the operating pressure.
    1. Using the ST, measure the operating pressure.
    2. Open the valve.
    3. Measure the operating pressure of control valve by turning steering wheel from stop to stop.

      Preparation tool: 

      ST1: PRESSURE GAUGE (925711000)

      ST2: ADAPTER HOSE B (34099AC020)

      ST3: ADAPTER HOSE A (34099AC010)

      G13648488Courtesy of SUBARU OF AMERICA, INC.

      Service limit: 

      8, 300 - 9, 000 kPa (85 - 92 kgf/cm2 , 1, 203 - 1, 305 psi)

    4. If it is out of specification, measure the steering effort. Refer to POWER ASSISTED SYSTEM (POWER STEERING)>GENERAL DIAGNOSTIC TABLE>INSPECTION>MEASUREMENT OF STEERING EFFORT (HYDRAULIC TYPE) .

      If it is not within specification, replace the control valve itself or control valve and pinion as a single unit, using new parts.

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