Sakai SW354, Shop Manual

Page: 430 / 480

10-081
TROUBLESHOOTING
3-4. Steering System
If a problem occurs in the steering systems such as the steering • charge pump and orbitrol, determine the cause
and carry out action as required, according to the following general troubleshooting items.
(NOTICE)
When checking whether or not the pressure is correct, refer to the pressure standard value for each
hydraulic circuit.
3-4-1. Steering wheel is hard to turn
Check point Cause Check/Action
1. Oil Level of
Hydraulic Oil Tank
Oil level in hydraulic oil tank is low. Fill tank until correct oil level is obtained.
2. Orbitrol Relief valve is open or setting pressure is
low.
Measure steering circuit pressure.
If low, check and clean relief valve or
replace it if necessary.
•
•
Flow to steering cylinder circuit is insufficient
due to leakage from check valve.
Check and clean check valve or replace it if
necessary.
Spool and sleeve of orbitrol are
contaminated or clearance is incorrect.
Check and clean orbitrol or replace it if
necessary.
3. Steering Circuit
Pressure
Pressure in return circuit from orbitrol
increases due to clogged charging hydraulic
filter.
Clean hydraulic filter or replace it if
necessary.
4. Steering Cylinder Cylinder thrust decreases due to internal
leakage of steering cylinder.
Repair steering cylinder or replace it if
necessary.
5. Suction Filter for
Steering • Charge
Pump
Steering • charge pump discharge rate
decreases due to clogged filter.
Clean suction filter or replace it if necessary.
6. Steering • Charge
Pump
Discharging pressure is insufficient due to
efficiency degradation of steering • charge
pump.
Measure steering circuit pressure.
If low, replace steering • charge pump.
•
•
7. Steering Column Column shaft and orbitrol shaft center are
misaligned.
Align column shaft with orbitrol shaft center
or replace it if necessary.
Column shaft bearing is worn or damaged. Repair column shaft or replace it if
necessary.
3-4-2. Steering response is slow
Check point Cause Check/Action
1. Oil Level of
Hydraulic Oil Tank
Oil level in hydraulic oil tank is low. Fill tank until correct oil level is obtained.
2. Orbitrol Oil is bypassing because relief valve is
open.
Measure steering circuit pressure.
If low, check and clean relief valve or
replace it if necessary.
•
•
3. Steering Cylinder Internal leakage of steering cylinder. Repair steering cylinder or replace it if
necessary.
4. Suction Filter for
Steering • Charge
Pump
Steering • charge pump discharge rate
decreases due to clogged filter.
Clean suction filter or replace it if necessary.
5. Steering • Charge
Pump
Discharging pressure is insufficient due to
efficiency degradation of steering • charge
pump.
Measure steering circuit pressure.
If low, replace steering • charge pump.
•
•
•