Maintenance; Fluid Level; Bleeding The Power Steering System; Bleeding Procedure - Isuzu 1999 RODEO Workshop Manual

4. Bleed the system. Refer to Bleeding the Power
Steering System in this section.
5. Start the engine and check the fluid level. Add power
steering fluid if required. When the engine is at
normal operating temperature, increase engine
speed to 1500 rpm.
CAUTION: Do not leave shutoff valve fully closed
for more than 5 seconds, as the pump could become
damaged internally.
6. Fully close the shutoff valve. Record the highest
pressures.
f If the pressure recorded is within 9300–9800 kPa
(1350–1420 psi), the pump is functioning within its
specifications.
f If the pressure recorded is higher than 9800 kPa
(1420 psi), the valve in the pump is defective.
f If the pressure recorded is lower than 9300 kPa
(1350 psi), the valve or the rotating group in the
pump is defective.
7. If the pump pressures are within specifications, leave
the valve open and turn (or have someone else turn)
the steering wheel fully in both directions. Record the
highest pressures and compare with the maximum
pump pressure recorded in step 6. If this pressure
cannot be built in either side of the power steering
unit, the power steering unit is leaking internally and
must be replaced.
8. Shut the engine off, remove the testing gauge.
9. Reconnect the pressure hose, check the fluid level
and make the needed repairs.
10. If the problem still exists, the steering and front
suspension must be thoroughly examined.

Maintenance

The hydraulic system should be kept clean and fluid level
in the reservoir should be checked at regular intervals and
fluid added when required.
Fluids and Lubricants in General Information section for
the type of fluid to be used and the intervals for filling.
If the system contains some dirt, flush it as described in
this section. If it is exceptionally dirty, the pump must be
completely disassembled before further usage. (The
steering unit cannot be disassembled.)
All tubes, hoses, and fittings should be inspected for
leakage at regular intervals. Fittings must be tight. Make
sure the clips, clamps and supporting tubes and hoses
are in place and properly secured.
Power steering hoses and lines must not be twisted,
kinked or tightly bent. Air in the system will cause spongy
action and noisy operation. When a hose is disconnected
or when fluid is lost, for any reason, the system must be
bled after refilling. Refer to Bleeding the Power Steering
System in this section.
f Inspect belt for tightness.
f Inspect pulley for looseness or damage. The pulley
should not wobble with the engine running.
f Inspect hoses so they are not touching any other
parts of the vehicle.
f Inspect fluid level and fill to the proper level.
Refer to Recommended
POWER–ASSISTED STEERING SYSTEM

Fluid Level

1. Run the engine until the power steering fluid reaches
normal operating temperature, about 55°C (130°F),
then shut the engine off.
2. Check the level of fluid in the reservoir.
3. If the fluid level is low, add power steering fluid as
specified in General Information to the proper level
and install the receiver cap.
4. When checking the fluid level after the steering
system has been serviced, air must be bled from the
system. Refer to Bleeding the Power Steering
System in this section.

Bleeding The Power Steering System

When a power steering pump or unit has been installed,
or an oil line has been disconnected, the air that has
entered the system must be bled out before the vehicle is
operated. If air is allowed to remain in the power steering
fluid system, noisy and unsatisfactory operation of the
system may result.

Bleeding Procedure

When bleeding the system, and any time fluid is added to
the power steering system, be sure to use only power
steering fluid as specified in General Information.
1. Fill the pump fluid reservoir to the proper level and let
the fluid settle for at least two minutes.
2. Start the engine and let it run for a few seconds. Do
not turn the steering wheel. Then turn the engine off.
3. Add fluid if necessary.
4. Repeat the above procedure until the fluid level
remains constant after running the engine.
5. Raise and support the front end of the vehicle so that
the wheels are off the ground.
6. Start the engine. Slowly turn the steering wheel right
and left, lightly contacting the wheel stops.
7. Add power steering fluid if necessary.
8. Lower the vehicle, set the steering wheel at the
straight forward position after turning it to its full steer
positions 2 or 3 times, and stop the engine.
9. Check the fluid level and refill as required.
10. If the fluid is extremely foamy, allow the vehicle to set
a few minutes, then repeat the above procedure.

Flushing The Power Steering System

1. Raise and support the front end of the vehicle off the
ground until the wheels are free to turn.
2. Remove the fluid return line at the pump inlet
connector and plug the connector port on the pump.
Position the line toward a large container to catch the
draining fluid.
3. While running the engine at idle, fill the reservoir with
new power steering fluid. Turn the steering wheel in
both directions. Do not contact or hold the steering
wheel to the wheel stops. This will cause the pump to
go to pressure relief mode, which may cause a
sudden fluid overflow at the reservoir.
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