GILLIG LOW FLOOR, Руководство по обслуживанию

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Hydraulic System
322
Power Steering Flow Test
Minimum Recommended Flow
With the engine running at the specified idle speed, vehicle stationary on the shop floor, and with a
normal load on the front axle, steer the wheels from full right to full left turn and observe the flow meter.
The flow must not fall below the minimum 3–4 GPM flow specification. Leave the gauge assembly
valve fully open.
Maximum Recommended Flow
Increase the engine speed to about 1,500 RPM and note the flow rate with the steering wheel station -
ary. Check this reading against the maximum flow rate (5 GPM) specifications. Excessive fluid flow can
cause damage to the internal parts of the steering gear. Leave the gauge assembly valve fully open to
measure the flow.
Keep your fingers clear of the axle stops and spacer block during this
test. Make sure that the spacer block contacts the axle stop squarely,
which will prevent breaking the axle stops or dangerous ejection of the
spacer block.
Leakage Test
If the supply pump is performing to specification, install a 1/2" spacer between the axle stops on one
side and turn the steering wheel hard in the direction necessary to pinch the spacer block. Record the
maximum pressure reading. The maximum pressure reading should be within 100 psi of the pressure
recorded in Step 5, Pressure Relief. Remove the spacer and repeat the test in the opposite direction,
recording the pressure.
If the pressure does not meet the recorded maximum pressure reading, the steering gear is worn inter-
nally and must be repaired or replaced.
The flow must be checked at normal operating temperature and with
a load on the front axle, or steering response complaints may not be
found. Inadequate flow will cause binding and uneven or intermittently
hard steering.