Hydraulic Flow and Pressure Test
HYDRAULIC FLOW AND PRESSURE TEST
WARNING: To prevent personal injury, safety goggles should be worn at all times while performing any test procedures on the power steering system.
The following procedure is to be used to test the operation of the power steering system on this vehicle. This test will provide the flow rate of the power steering pump along with the maximum relief pressure. This test is to be performed any time a power steering system problem is present to determine if the power steering pump or power steering gear is not functioning properly. The following flow and pressure test is performed using the Power Steering Analyzer Kit, Special Tool 6815, hoses, Special Tools 6905 and 6959, and adapters, Special Tool 8185A.
1. Assemble hoses on Power Steering Analyzer as shown. Install Pressure Hose (2), Special Tool 6959, in inlet fitting (gauge end) of Power Steering Analyzer flow meter (1). Install Pressure Hose (4), Special Tool 6905 (in 6893 kit), into outlet fitting (valve end) of Power Steering Analyzer flow meter (1). Install Pressure Hose, Special Tool 6713 (in 6815 kit) on 6905 (4).
2. Install Adapter, Special Tool 8185-1A, in end of Pressure Hose, Special Tool 6713.
3. Install Adapter (3), Special Tool 8185-2, in end of Pressure Hose, Special Tool 6959 (2).
4. Raise and support vehicle. Maintenance
5. Unscrew tube nut and remove power steering fluid pressure hose (3) from power steering gear (1) lower port.
6. Thread vehicle's power steering pressure hose (3) into Adapter (4), Special Tool 8185-2, connected to Analyzer Hose. Tighten tube nut to 31 Nm (23 ft. lbs.). Route hoses away from exhaust system as well as other unfriendly surfaces.
7. Thread Adapter (6), Special Tool 8185-1A, connected to Analyzer hose, into open power steering gear lower port. Tighten tube nut to 31 Nm (23 ft. lbs.). Route hoses away from exhaust system as well as other unfriendly surfaces.
8. Being careful not to kink or pinch Analyzer hoses, lower vehicle to ground level.
TEST PROCEDURE
1. Completely open valve on Power Steering Analyzer flow meter.
2. Start engine and let idle long enough to circulate power steering fluid through Analyzer and hoses, until all air is out of fluid. Shut off engine.
3. Check power steering fluid level and add fluid as necessary. Start engine again and let idle.
4. The Analyzer gauge should read below 300 psi (2068 kPa). If above, inspect hoses for restrictions and repair as necessary. The initial pressure should be in range of 100-175 psi (689-1896 kPa). The flow meter should read above 1.5 GPM (5.7 LPM).
CAUTION: The following test procedure step involves testing maximum pump pressure output and flow control valve operation. Do not leave valve closed for more than five seconds as the pump could be damaged.
NOTE: Power steering pump maximum pressure is 1,400 - 1,500 psi (9,653 - 10,342 kPa).
5. Close flow meter valve fully three times and record highest pressure indicated each time. All three readings must be within specifications. If any of readings are not within specifications, replace pump. Power Steering Pump - Removal
CAUTION: During the next step, do not force the pump to operate against the stops for more than 4 seconds at a time as pump damage may result.
6. Once pump has been verified as functioning correctly, completely open valve on Power Steering Analyzer flow meter. Turn steering wheel to extreme left until stop in steering gear is met. Hold it there for 2 - 4 seconds, then release it. Now turn steering wheel to right until right stop is met. Hold it there for 2 - 4 seconds, then release it. Record stabilized pressure at each position. Compare recorded readings to specifications. If output pressures are not within 100 psi (689 kPa) of one another or are below specifications steering gear is leaking internally and must be replaced. Steering Gear - Removal
NOTE: Before installing power steering hose on power steering gear, wipe clean connections with a lint-free cloth and replace O-ring. Lubricate O-ring using clean power steering fluid.
7. Remove special tools and reconnect pressure hose. Tighten tube nut to specifications. Specifications
8. Fill and bleed system. Service and Repair