Sakai SV201-1, Shop Manual

Page: 229 / 238

9-052
TROUBLESHOOTING
3-2-3. Slow machine speed or small drive force 2/2
Check point Cause Check/Action
6. Propulsion Pump Discharge flow rate is insufficient due to
efficiency degradation of propulsion pump.
Measure discharge flow rate of propulsion
pump with flow meter.
If discharge flow rate is not within specified
range, repair propulsion pump or replace it
if necessary.
•
•
Discharge flow rate is insufficient due to
wear of propulsion pump drive shaft splines.
Replace propulsion pump.
Propulsion circuit pressure is not held in
propulsion pump case.
If pressure in propulsion pump case is not
within allowable range, repair propulsion
pump or replace it if necessary.
3-2-4. Machine does not stop completely with F-R lever in “N”
Check point Cause Check/Action
1. F-R lever Linkage F-R lever linkage is faulty. Check and adjust F-R lever linkage or
replace it if necessary.
2. Servo Control
Valve
Servo control valve neutral position
adjustment failure.
Check and adjust servo control valve or
replace it if necessary.
3. 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. Propulsion Circuit
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, inspect relief valve or replace it if
necessary.
•
•
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.
•
•
4. Hydraulic Oil Filter Load of charge pump increases due to
clogged filter, causing temperature of
hydraulic oil in circuit to rise.
Clean hydraulic oil filter or replace it if
necessary.
Charge circuit pressure increases due to
clogged filter.
Clean hydraulic oil filter or replace it if
necessary.