Pressure testing of the power steering system
Necessary equipment
- KM-354-B Pressure Testing Measuring Kit
Check the fluid pressure as follows to determine whether the problem is in the pump or in the steering gear.
Verification procedure
1. Check the power steering fluid level and the power steering pump drive belt tension. See "Checking the level and refilling the fluid" in this section and section 6B, "Power Steering Pump".
2. Disconnect the high pressure tube from the pump. Collect the leaking liquid in a small container.
3. Connect the hose of the KM-354-B pressure test kit to the high pressure hose from the power steering pump.
4. Set the gear selector lever to the PARK position (cars with automatic transmission complete with final drive) or NEUTRAL (vehicles with manual transmission complete with final drive). Apply the parking brake.
5. Open the check valve fully.
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.
8. Increase engine speed to 1500 rpm.
Note: If the valve is completely closed for more than 5 seconds, the power steering pump may be damaged.
9. Close the control valve completely and read the pressure value. The pump pressure with the valve closed should be approximately 8500 kPa (1233 psi).
10. Close the control valve completely and read the pressure value. The pump pressure with the valve closed should be approximately 8500 kPa (1233 psi).
11. Open the check valve fully immediately.
12. Turn the steering wheel left and right until it stops. If the pressure is within the specified range, the problem is not with the pump. Check for leaks from the power steering gear.
Checking for leaks in the power steering system
Please perform the following checks:
- Liquid tank overflow.
- Presence of air in the liquid and overflow.
- Reliability of hose connections.
- No leakage from the torsion bar, steering shaft and regulator seals.
- No damage to the sealing surfaces of the parts.
Important: Identify the exact location of the leak. The location where the fluid is dripping is not necessarily the location of the leak in the system. If service is required after disassembly, clean the leak, replace the leaking seal, check for damage to the sealing surfaces, and tighten the bolt to the specified torque if necessary.
External leak test
This procedure is designed to find the exact location of the leak. In some cases, it is easy to find the leak, but it can be quite difficult to find a leak of the seepage type. To find the leak, use the following method:
1. With the engine off, wipe dry the entire power steering system.
2. Check the power steering fluid level in the pump reservoir. Correct the fluid level if necessary. See "Checking the level and refilling the fluid" in this section.
Note: Do not hold the steering wheel on the stop for even a second, as this may damage the power steering pump.
3. Start the engine. Turn the steering wheel all the way to the right and left several times.
4. Start the engine. Turn the steering wheel all the way to the right and left several times.
5. Find the exact location of the leak and fix it.