Relief Pressure Test (All Others)
- Close shut-off valve completely 3 times. Record highest pressure attained each time.CAUTION: DO NOT leave shut-off valve closed more 5 seconds, as this could damage the pump.
- If recorded pressures are within specifications and range of readings are within 50 psi (3 kg/cm2
), pump is working properly. See POWER STEERING PUMP PRESSURE TEST SPECIFICATIONS
table. If recorded pressures are high but do not repeat within the 50 psi (3 kg/cm2
) range, flow control valve in pump is sticking.NOTE: For power steering pump applications, refer to the POWER STEERING PUMP APPLICATION table.
- On ZF pump, replace pump. On Saginaw pump, remove and inspect flow control valve. For removal and disassembly, see STEERING GEAR - POWER article in the STEERING section. On Saginaw pump, if recorded pressures are constant but less than specified, clean or replace pressure relief and flow control valve assembly. For removal and disassembly, see STEERING GEAR - POWER article.CAUTION: To prevent scrubbing flat spots on tires, DO NOT turn steering wheel more than 5 times without rolling vehicle.
- If pressures are still low, overhaul Saginaw pump or replace ZF pump. If pump pressures are within specifications, leave shut-off valve open and turn steering wheel from stop-to-stop, with engine idling. Record highest pressure attained at each wheel stop and compare readings with maximum pump pressure previously recorded.
- If this pressure cannot build up in either side of gear, gear is leaking internally and must be disassembled and repaired. For removal and disassembly, see STEERING GEAR - POWER article.