Power Steering Pump Flow and Pressure Test
Pump Flow and Pressure TestWARNING: Do not touch the flowmeter during the test procedure or severe burns and serious injury may occur.
1. CAUTION: Make sure that the connection point will not interfere with any of the engine accessory drive components or drive belts.
Install the Power Steering Analyzer at the high pressure port of the power steering pump. Make sure the power steering analyzer gate valve is fully open.
^ On some vehicles, the power steering pump high pressure port is inaccessible, and therefore, the power steering analyzer should be installed either at the steering gear or at a point in the high pressure line between the power steering pump and the steering gear.
2. Place a Dial Thermometer in the power steering pump reservoir.
3. Check the power steering fluid level. If necessary, add power steering fluid.
^ Use Motorcraft MERCON Multipurpose (ATF) Transmission Fluid XT-2-QDX or equivalent meeting Ford specification MERCON.
4. Install the digital tachometer.
5. CAUTION: Do not hold the steering wheel against the stops for more than three to five seconds at a time. Damage to the power steering pump will occur.
Start the engine. Place the transmission in N (NEUTRAL). Set the parking brake. Raise the power steering fluid temperature to 74 - 80°C (165 - 175°F) by rotating the steering wheel fully to the left and right several times.
6. Set the engine speed to idle. Record the flow rate and pressure readings.
^ If the flow rate is below the idle flow rate specification, the power steering pump may require repair. Continue with the test procedure.
^ If the pressure reading is above the idle pressure specification, then check power steering hoses for kinks and restrictions.
7. Partially close the gate valve to obtain 5,175 kPa (750 psi). Record the flow rate.
^ If the flow rate is less than the specified flow rate, install a new power steering pump.
8. CAUTION: Do not allow the gate valve to remain closed for more than five seconds.
Completely close and partially open the gate valve three times. Record the pressure relief valve actuation pressure reading.
^ If the pressure does not meet the relief pressure specification, install a new power steering pump.
9. Set the engine speed to 1,500 rpm. Record the flow rate.
^ If the flow rate varies more than 3.785 liters/minute (1 gallon/minute) from the initial flow rate reading, install a new power steering pump.
10. CAUTION: Do not hold the steering wheel against the stops for more than three to five seconds at a time. Damage to the power steering pump will occur.
Set the engine speed at idle. Turn (or have an assistant turn) the steering wheel to the left and right stops. Record flow rate and pressure readings at the stops.
^ The pressure reading at both stops should be nearly the same as the maximum pump relief pressure.
^ The flow rate should drop below 1.9 liters/minute (0.5 gallon/minute).
^ If the pressure does not reach the maximum pump relief pressure or the flow rate does not drop below the specified value, excessive internal leakage is occurring. Install a new steering gear as necessary.
11. Turn (or have an assistant turn) the steering wheel slightly in both directions and release it quickly while watching the pressure gauge.
^ The pressure reading should move from the normal backpressure reading and snap back as the steering wheel is released.
^ If the pressure returns slowly or sticks, the rotary valve in the steering gear is binding. Check the steering column and linkage before installing a new steering gear.