TM 5-3805-290-23-1
STEERING SYSTEM TESTS, INSPECTIONS, AND ADJUSTMENTS - CONTINUED
0016 00
PUMP PERFORMANCE (STEERING) TEST
0016 00
N OT E
This test should be used to help determine if there is a problem with steering pump. Pump performance
should be checked if machine has slow steering times.
Steering time is affected by amount of oil flow produced by steering pump. Check steering times to determine
if there is a problem with steering pump.
1.
Start engine and warm hydraulic oil to normal operating temperature. Raise work tool slightly off ground (TM 5-3805-
290-10).
2.
Maintain engine speed at high idle (TM 5-3805-290-10).
3.
Record steering time from stop to stop. At high idle, steering cycle time should be 1.6 seconds.
N OT E
While parking brake is disengaged, difference between left turn and right turn must not differ by more
than 0.3 seconds. While parking brake is engaged, difference between left turn and right turn should
increase by no more than 0.2 seconds.
4.
Lower work tool flat on ground (TM 5-3805-290-10).
5.
Reduce engine speed to low idle (TM 5-3805-290-10).
6.
Record steering time from stop to stop. At low idle, steering cycle time should be 3.7 seconds.
7.
Stop engine (TM 5-3805-290-10).
8.
Compare recorded cycle times with proper cycle times. If cycle times match, steering pump is working properly.
a.
If cycle times do not match, one of these conditions may be present:
(1)
Pressure setting for backup relief valve is not within specifications.
(2)
Pump is not upstroking.
(3)
Pump may have excessive wear.
b.
Measure main relief pressure (WP 0017 00). If main relief pressure is low, cycle times should be retested after
main relief pressure has been corrected.
c.
Test pressure of steering pump to ensure pump is upstroking (refer to Piston Pump (Steering and Pilot) High Pres-
sure Stall Test and Adjustment in this work package).
d.
Pump may have excessive wear. If so, replace pump (WP 0182 00).
e.
If cycle time is slow for only one steering circuit, circuit with slow cycle time should be tested for one of these
conditions:
(1)
Low relief valve setting.
(2)
Leak in circuit.
(3)
Control spool that is not shifting fully.
f.
If steering cycle times are consistently slow in one direction, replace secondary steering relief valve (WP 0104 00).