Sakai SW800-II, Shop Manual

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10-077
TROUBLESHOOTING
3-2-4. Vehicle does not stop completely with forward-reverse lever in neutral position
Check point Cause Check/Action
1. Propulsion Pump
Servo Cylinder
Faulty propulsion pump servo cylinder or
faulty pump swash plate setting.
Repair propulsion pump or replace it if
necessary.
3-2-5. Propulsion system is overheating
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. Oil Cooler Cooling efficiency is reduced due to clogged
oil cooler fins.
Clean oil cooler fins.
3. Flushing Valve Hydraulic oil in propulsion closed circuit is
insufficiently cooled due to flushing valve
shuttle spool sticking.
Repair flushing valve or replace it if
necessary.
Hydraulic oil in propulsion closed circuit is
insufficiently cooled because flushing valve
relief setting pressure is excessively high.
Adjust flushing valve relief setting pressure
or replace it if necessary.
4. Propulsion Circuit
Setting Pressure
If circuit pressure setting is excessively low,
relief valve opens, causing temperature of
hydraulic oil in circuit to rise.
Measure propulsion circuit pressure. If low,
increase relief setting pressure.
If load is excessively heavy, relief valve
opens, causing temperature of hydraulic oil
in circuit to rise.
Measure propulsion circuit pressure. If high,
decrease propulsion load.
5. Suction Filter for
Charge Pump
Load of charge pump increases due to
clogged filter, causing temperature of
hydraulic oil in circuit to rise.
Clean suction filter or replace it if necessary.
6. Charge Line Filter Charge circuit pressure increases due to
clogged filter.
Clean line filter or replace it if necessary.
3-2-6. Abnormal noise from propulsion system
Check point Cause Check/Action
1. Axle Bearings Axle bearings supporting front drum and
rear drum are damaged.
Replace axle bearings.
2. Hydraulic Hose
Clamp
Vibrator sound of hydraulic hose is
generated because clamp securing
hydraulic hose is loose.
Tighten bolts of loose hydraulic hose clamp
to specified torque.
3. Suction Filter for
Charge Pump
Cavitation is occurring in charge pump due
to clogged filter.
Clean suction filter or replace it if necessary.
4. Charge Circuit
Pressure
If charge pressure is low, brake cannot be
released completely, which causes brake
drag.
Measure charge pressure. If low, check
and adjust charge relief valve or replace it if
necessary.
5. Propulsion Motor Internal bearing of propulsion motor is
damaged.
Repair propulsion motor or replace it if
necessary.