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

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

Special Tools Required

- P/S Joint Adapter Plate (Pump) 07ZAK-S7CA100
- P/S Joint Adapter (Hose) 07ZAK-S7CA200
- P/S Pressure Gauge 07406-0010001
- P/S Joint Adapter (Pump) 07VAK-P8A011A

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

1. Check the power steering fluid level Service and Repair.

2. Disconnect the pump outlet hose (A) from the pump outlet with care so as not to spill the power steering fluid on the frame and other parts, then install the P/S joint adapter (pump) on the pump outlet (B) with the P/S joint adapter plate.





3. Connect the P/S joint adapter (hose) to the P/S pressure gauge, then connect the pump outlet hose to the P/S joint adapter (hose).

4. Install the P/S pressure gauge to the P/S joint adapter (pump).

5. Fully open the shut-off valve (A).





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

7. Start the engine, and let it idle.

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

9. 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 high, check for:

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

10. Let the engine idle, and gradually close the shut-off valve and immediately 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.


11. Immediately open the shut-off valve fully. If the pump is in good condition, the gauge should read at least 8,150-8,850 kPa (83-90 kgf/cm2, 1,181-1,280 psi). A low reading means the pump output is too low for full assist. Repair or replace the pump.