Operation & Maintenance Manual
──
LG968 /969Wheel Loader
88
3.8.5 Steering System
No. Problems
Possible
Causes
Remedy
1
Heavy steering
1
Insufficient oil supply for working pump
and steering pump
2
Air in steering system
3
Faulty of steel-ball in check valve body of
steering unit causes heavy steering and
little pressure during either slow or quick
turning of steering wheel.
4
Faulty of piloted valve
5
Too low pressure of safety valve
1
Check oil pump
2
Discharge air from system and
check the suction lines
3
Check the valve. Clean if it is
blocked by dirt
4
Replace piloted valve
5
Readjust the pressure to
specified value
2
Increased
steering turns
1
Over low oil level in hydraulic reservoir
2
Leakage of oil lines, damaged oil seals
3
Internal leakage of steering cylinder
4
Worn steering unit
5
High viscosity of oil or wrong brand of oil
1
Fill oil to specified level
2
Change seals of oil circuits
3
Change seals of hydraulic tanks
4
Replace steering unit
5
Change by the specified oil
3
Inflexible or
failure of
steering system
1
Damaged spring plate of steering unit
2
Cracked, broken or deformed centre pin
and drive shaft
3
Faulty dual overload valve
4
Scuffed rotor and stator, scuffed valve
spool, valve body and sleeve
5
Faulty in steering pump or piloted valve
1
Change the damaged spring
plate
2
Change the center pin or drive
shaft
3
Check and repair the
bi-directional overload valve
4
Disassemble, check, clean and
assemble strictly or change parts
5
Change the damaged parts
4
Steering wheel
can not reset
1
No concentric steering column and valve
spool
2
Steering shaft axially locks the valve plug
3
Large axial resistance of steering column
4
Broken spring plate
Phenomena: medium pressure drop
increases or the relief of steering unit fails
when steering wheel stops (wheel loader
deflects from straight traveling line)
Remove the problems according to
the respective reasons.
3.8.6 Engine
Refer to
“Operation and Maintenance Manual”
of diesel engine for troubleshooting
.
