Hummer H1 Service Manual page 514

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13. Turn steering wheel lightly against each stop and record
maximum pressure.
a. If pressure at each stop is about the same as recorded
in step 10, and flow drops to 0.5 gpm (1.85 L/min.),
continue with test.
b. If pressures does not reach maximum recorded in step
10, and flow rate does not fall off, overhaul steering
gear to correct internal leakage in valve, or past seal
rings.
14. Turn steering wheel to the right, release it., and observe
the analyzer gauge. Then turn the wheel to the left, release
it, and observe the gauge again.
a. If the gauge needle indicates normal pressure then
snaps back as the wheel is released. Continue the test.
b. If the gauge indicates normal pressure but the needle
is slow to return when the wheel is released, the steer-
ing gear valve body or spool is sticking. Overhaul will
be required to correct the problem.
15. If gear and pump test OK but a problem still exists, check
for fluid contamination. Draw off sample with suction gun
and empty sample in glass container.
fluid, foreign material, fluid layering (fluid separates into
two layers), foreign material/metal particles in the fluid.
Any of these conditions will cause gear and pump
problems. Flushing the system with new fluid may correct
the problem.
16. If fluid condition is OK but a problem still exists, a
problem may exist in the steering linkage, tires/wheels, or
suspension part. Further diagnosis will be required.
FITTING
ADAPTERS
ANALYZER
J-25323
Figure 8-30: Analyzer Pressure Test Connections
05745159
POWER STEERING GEAR DISASSEMBLY AND
OVERHAUL
Cleanliness is extremely important to a successful gear over-
haul. Clean the gear exterior before disassembly and make sure
the workbench area is clean and dry. Drain as much of the old
fluid from the gear as possible beforehand. Dirt and foreign
material must not be allowed to enter the gear internal compo-
nents. Use lint free shop towels for wiping parts and hands
clean. Lint from cotton towels will flow through the system
and eventually cause the valve body spool, or pump control
valve to stick and bind.
Side Cover and Pitman Shaft Removal
1. Remove side cover attaching bolts.
2. Hold adjuster screw with hex wrench and remove adjuster
screw nut.
3. Rotate stub shaft as necessary to center pitman shaft teeth
in rack piston. Use 12 point socket and ratchet to turn stub
shaft.
4. Remove pitman shaft, side cover, and gasket (Figure 8-31).
Look for burned
ADJUSTER
LOCKNUT
ADJUSTER
SCREW
Steering System
GASKET
PITMAN
SHAFT
Figure 8-31: Side Cover and Sector Shaft
8-23
SIDE
COVER
4-1-00