Hydraulic Power Steering Pump Pressure Test With T/N 07406-001000A Or T/N 07406-001A101

Hydraulic Power Steering Pump Pressure Test with T/N 07406-001000A or T/N 07406-001A101

Special Tools Required

- P/S Joint Adapter (Pump) 07VAK-P8A011A
- P/S Joint Adapter Plate (Pump) 07ZAK-S7CA100
- P/S Joint Adapter (Hose) 07ZAK-S7CA200
- P/S Pressure Gauge 07406-001000A or 07406-001A101

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 Testing and Inspection.

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) and P/S joint adapter plate (pump) on the pump outlet (B).





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 pressure control valve (A).





6. Start the engine and let it idle.

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

8. 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 (15.0 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 Overhaul or replace the pump assembly Removal and Replacement.

9. Raise the engine speed to 3,000 rpm, and measure the fluid pressure. If the pump is in good condition, the gauge should read no more than 1,470 kPa (15.0 kgf/cm2, 213 psi). If the gauge reads higher, repair or replace the pump.

10. 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.

11. Immediately open the shut-off valve fully. If the pump is in good condition, the gauge should read at least 7,460-8,140 kPa (76-83 kgf/cm2, 1,080-1,180 psi).A low reading means pump output is too low for full assist. Repair or replace the pump.