Hydraulic Power Steering Pump Pressure Test With T/N 07406-0010001 (Without EPS)

Hydraulic Power Steering Pump Pressure Test with T/N 07406-0010001

Special Tools Required

- Pump Joint Adapter 07RAK-S040111 or 07RAK-S040110
- Hose Joint Adapter 07RAK-S040122
- P/S Pressure Gauge 07406-0010001

Check the fluid pressure as follows to determine whether the trouble is in the pump or the steering gearbox.

1. Check the power steering fluid level .

2. Remove the cowl cover and under-cowl panel Service and Repair.

3. Remove the pump outlet hose clamp (A) from the intake manifold.






4. Disconnect the pump outlet hose, then install the pump joint adapter on the pump (A). Take care so as not to spill the power steering fluid on the frame and other parts.





5. Install the P/S pressure gauge to the pump joint adapter.

6. Connect the hose joint adapter to the P/S pressure gauge.

7. Connect the pump outlet hose (A) to the hose joint adapter.






8. Open the shut-off valve (A) fully.





9. Fully open the pressure control valve (B).

10. Start the engine, and let it idle.

11. Turn the steering wheel from lock to lock several times to warm the fluid to operating temperature at 158 °F (70 °C).

12. Measure steady-state fluid pressure while the engine is idling. If the pump is in good condition, the gauge should read no more than 1,470 kPa (15 kgf/cm2, 213 psi).

If the reading is low, check for:

- Clogged or deformed inlet hose.
- Clogged power steering reservoir filter.

If the reading is high, check for:

- Clogged or deformed inlet or return line between the pump and the steering gearbox.
- Clogged valve body unit.

If the inlet hose and power steering reservoir are OK, repair or replace the pump assembly .

13. Raise the engine speed to 3,000 rpm, and measure the fluid pressure. If the pump is in good condition, the gauge should read at least 1,470 kPa (15 kgf/cm2, 213 psi). If the reads higher, repair or replace the pump.

14. Close the shut-off valve gradually until the pressure gauge needle is stable. Read the pressure.

NOTICE
Do not keep the shut-off valve closed more than 5 seconds or the pump could be damaged by over-heating.

15. Immediately open the shut-off valve fully. If the pump is in good condition, the gauge should read at least 7,850-8,550 kPa (80-87 kgf/cm2, 1,140-1,240 psi). A low reading means pump output is too low for full assist. Repair or replace the pump.