HYDRAULICS
8L-55
POWER STEERING SYSTEM TEST
The purpose of this test is to determine if the steering
cylinder and the steering unit are operating properly
(Figure 8L-2).
Figure 8L-2. Steering Unit
1. With the engine running, turn the steering wheel
all the way right and then all the way left.
Conclusion
• If the steering wheel becomes hard to turn or stops
turning and a hissing sound is heard after steering
the maximum right and/or left, the steering unit is not
at fault.
• If the steering wheel continues to turn, proceed with
the test.
2. Remove both hydraulic hoses from the steering
cylinder (Figure 8L-3), plug the hoses and cap the
cylinder ports.
Figure 8L-3. Steering Cylinder
3. Turn the steering wheel all the way to the right and
then all the way left.
Conclusion
• If the steering wheel becomes hard to turn or stops
turning, the cylinder is at fault and should be
repaired or replaced.
• With steady hand pressure on the steering wheel,
the steering wheel should not make a complete
revolution within 30 seconds.
• If the steering wheel makes a complete revolution
within the 30 seconds, steering valve is faulty.
4. Perform steering circuit test under Hydraulic
Instrument Test in (Section 8M).
NOTICE
Before performing the test, check the steering sys-
tems for mechanical binding and damage that may
affect the steering.
Steering
Column
Steering
Unit
NOTICE
Hose plugs must be capable of withstanding steering
system hydraulic pressures.