Troubleshooting - Hyundai HSL1500T Wheel Manual

4. 14 TROUBLESHOOTING

1. Hydraulic System
Problem
Loss of hydraulic power (no flow
from gear pump)
Loss of hydraulic power (flow from
gear pump)
Hydraulic action jerky
Hydraulic Overheat
Lift arms raise slowly at full engine
RPM
Lift or tilt cylinders will not support
a load
Contact Authorized Equipment Dealer for all major fixes under the remedy column except for regular service (ie. Replenish fluids,
tightening etc.)
4. MAINTENANCE
Cause
Reservoir low on fluid
Coupling between engine and pump
failure
Spline coupling failure between front
and rear hydrostatic pump
Hydraulic gear pump not functioning
Reservoir low on fluid
Foot pedal linkage disconnected or
binding
Auxiliary hydraulics engaged
Relief valve failure in control valve
Reservoir low on oil
Air in hydraulic system
Anticavitation check valve not
functioning
Engine fan not turning
Incorrect temperature sensor
Reservoir low on fluid
Oil cooler plugged or dirty (also
check engine radiator)
Auxiliary engaged
Reservoir low on oil
Foot pedal linkage binding
Auxiliary engaged
Engine RPM too slow
Anticavitation check valve spring
broken
Main relief or port relief valve in
control valve faulty
Internal leakage in pump due to wear
Oil bypassing one or both lift
cylinder piston seals
External leak between or at control
valve and cylinders
Control valve spool not centering
Oil leaking by one or both cylinder
piston seals
Remedy
Replenish with 10W30 API SJ oil.
Check for hose or fitting leaking.
Inspect and replace damaged parts.
Check for misalignment between
engine and pumps.
Inspect coupling for sheared splines.
Also check pump shaft bearings.
Inspect and repair.
Replenish with 10W30 API SJ oil.
Inspect and adjust.
Disengage.
Check pressure and adjust.
Replenish with 10W30 API SJ oil.
Check for leak between reservoir
and pump. Bleed system by
extending and retracting lift
cylinders several times.
Inspect and repair or replace.
Inspect fan v-belt. Adjust or replace.
Replace.
Replenish with 10W30 API SJ oil.
Clean cooling fins.
Disengage.
Replenish with 10W30 API SJ oil.
Inspect and adjust.
Disengage.
Check RPM and reset.
Replace.
Check pressure, if necessary - adjust.
Check pump flow and repair or
replace as necessary.
Install new piston seal kits.
Check for leaks and correct.
Check for sticking foot pedal
linkages.
Check for broken or stuck return
spring on valve spool.
Install new piston seal kits.
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