- The power steering system test is a method used in order to identify
and isolate hydraulic circuit difficulties. Prior to performing this test,
make the following inspection and the necessary corrections.
- Inspect the pump reservoir for the proper fluid level. Refer to
Checking and Adding Power Steering Fluid
.
- Inspect the pump belt for proper tension. Refer to
Drive Belt Replacement
4.3L or
Drive Belt Replacement
4.8L,5.3L,6.0L
in Engine Mechanical.
- Inspect the pump drive pulley condition. Refer to
Drive Belt Idler Pulley Replacement
4.3L
or
Drive Belt Idler Pulley Replacement
4.8L,5.3L,6.0L in Engine Mechanical.
Notice: Do not leave the valve fully closed for more than 5 seconds, or the
pump could be damaged internally.
Important: Perform all the tests with the engine idling at the normal operating
temperature.
Important: In order to prevent scrubbing flat spots onto the tires, do not turn
the steering wheel more than 5 times without rolling the vehicle in order
to change the tire-to-floor contact area.
- Perform the following procedure:
5.1. | Place a container under the steering gear or the pump in order
to catch the fluid when disconnecting or connecting the hoses. |
5.2. | With the ignition OFF, disconnect the pressure hose at the steering
gear or at the power steering pump. |
5.2.1. | Install the J 5176-D
to both hoses. |
5.2.2. | Position the gauge between the shutoff valve (2) and the pump. |
5.2.3. | Open the shutoff valve (2). |
5.3. | Remove the filler cap from the pump reservoir. Inspect the fluid
level. |
5.3.1. | Fill the pump reservoir with power steering fluid to the full
mark on the dipstick. |
5.3.2. | While momentarily holding the steering wheel against the stop,
start the engine and inspect the connections at the J 5176-D
for leaks. |
5.5. | Insert the J 5421-02
in the reservoir filler opening. |
Move the steering wheel from stop to stop several times until the thermometer
indicates the power steering fluid in the reservoir has reached a temperature
of 65°-77°C (150°-170°F).
5.6. | Start the engine. Inspect the pump fluid level. |
5.6.1. | Add power steering fluid, if required. |
5.6.2. | When the engine is at normal operating temperature, the initial
pressure reading on the gauge, with the valve open, should be in the 550-1034 kPa
(80-150 psi) range. |
5.6.3. | If this pressure is in excess of 1380 kPa (200 psi),
inspect the hoses for restrictions. |
5.6.4. | Inspect the poppet valve for proper assembly. |
5.7. | Fully close the gate valve 3 times. |
Record the highest pressures attained each time.
• | If the pressures recorded are within 9,308-9,998 kPa
(1,350-1,450 psi) and the range of readings are within 345 kPa
(50 psi), the pump is functioning within specifications. |
• | If the pressures recorded are high, but do not repeat within 345 kPa
(50 psi), the flow controlling valve is sticking. |
• | Remove any burrs using a crocus cloth or a fine hone. |
• | Flush the system if the system contains dirt. |
• | If the system is exceptionally dirty, disassemble the pump and
the gear. |
• | Clean, flush, and reassemble the system before further usage. |
• | If the recorded pressures are constant but between 690 kPa
(100 psi) and 9,308 kPa (1,350 psi), replace the flow
control valve. Inspect the system. |
• | Replace the rotating group in the pump if the pressures remain
low. |
5.8. | If the pump pressures are within specifications, leave the valve
open and turn the steering wheel to both stops. |
5.9. | Record the highest pressures. Compare the pressures with the maximum
pump pressure recorded. |
If this pressure cannot be reached in at least one side of the gear,
the gear is leaking internally.
Disassemble and repair the gear.
5.10. | Shut the engine OFF. |
5.11. | Remove the testing gauge. |
5.12. | Reconnect the pressure hose. |
5.13. | Inspect the fluid level. |
Make the necessary repairs.
5.14. | If the problem still exists, examine the steering and the front
suspension. |