Power Steering Pump: Testing and Inspection

Fig. 5 Power steering pump oil pressure test connections:

CHECKING PUMP PRESSURE

With pump reservoir filled with oil to the proper level, turn steering wheel several times from one extreme to the other until all air is bled from the system. Air in the system will be indicated by bubbles in the reservoir.
1. Disconnect pressure hose at power steering pump. Position a small container under hose connection to catch any fluid which may leak.
2. Connect tool No. J-5176-21 to power steering pump hose connection, Fig. 5.
3. Install adapter fitting J-5176-22 and pressure gauge J-5176-02, then connect power steering hose to gauge, Fig. 5.
4. Open gauge valve, then start engine and allow to reach operating temperature and check power steering pump fluid level.
5. With engine at operating temperature and pressure gauge valve opened, pressure should be 80 to 125 psi. If pressure is above 200 psi, check gauge and valve for proper installation and power steering hoses for restrictions.
6. Fully close and open valve three times and record highest pressure obtained each time. Do not leave valve closed for more than 5 seconds, as damage to pump may result. Pump pressure should be a minimum of 1000 psi. If the three pump pressure readings are within 50 psi, the pump is functioning properly. If readings are high but not within 50 psi of each other, the pump flow control valve is sticking. If readings obtained are more than 100 psi lower than the specified pressure, replace the pump flow control valve and recheck control pressure. If pressures are still low, replace pump rotor and vanes.
7. If pump pressures are within specifications, leave pressure gauge valve open and turn steering wheel from lock to lock, noting pressures at each stop. If pressures at both stops are not the same as obtained in step 6, the steering gear is leaking internally and should be disassembled and repaired.
8. Turn off engine and remove test gauge and adapters, then connect hose and check pump fluid level.