Power Steering Trouble Shooting Guide
Test Equipment
 
TEST EQIPMENT
 

There are many good integrated hydraulic test kits on the market incorporating pressure and flow gauges and thermometers. These can be expensive and if their price is not justified by the work load, a satisfactory set of gauges can be built up over a period of time.

Figure 6 shows a typical installation of a test kit in the hydraulic circuit. If a combination Flow and pressure gauge and shut off valve is not available then a commercially available pressure gauge and hydraulic gate valve will be of value
Figure 6 - Typical Test Circuit
 
 
Pressure Gauge
 
A good quality pressure gauge is essential and is probably the most important piece of test equipment. Any good quality gauge reading to 17,500 kpa (2500 psi) will do. This pressure range will cover most cars & trucks, however, if much of your work is on systems with peak pressures of up to 8,00 kpa (1200 psi) then it would be worth considering using a 0-10,000 kpa (0-1500 psi) gauge. The larger dial face the better. The gauge is placed in the line from the pump to the steering gear using a suitable "T" piece.
 
Hydraulic Test Valve
 

A hydraulic valve with a Row capacity of at least 25 I/min (6 gpm), without significant restriction, is placed in the line from the pump to the steering gear, down stream of the gauge. The purpose of the test valve is to stem the flow from the pump, forcing it into relief. The pump's relief pressure can then be read at this point.

Flow meter

A flow meter, measuring up to 40 I/min (10 GPM) is placed in series with the pump to steering gear pressure line, between the shut off valve and the pressure gage. The flow gauge is used to measure minimum, or idle flow rates and maximum flow rates. Maximum flow rates are necessary to determine if the flow control circuit is performing satisfactorily.

Thermometer

A stem dial type thermometer is a useful tool when trouble shooting. It is essential to bring the system to correct operating temperature prior to conducting tests.

Tension Wrench - Dial type

Dial type tension wrenches are used to apply measured amounts of input torque to the steering gear input shaft. The wrench must be able to read torque, both clockwise and anti clockwise, up to 20 Nm {150 in/lbs.). The wrench is also useful in determining levels of column friction and joint phasing.