Sakai SV540 Series, Shop Manual

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9-091
TROUBLESHOOTING
3-2-3. Slow machine speed or small drive force 2/2
Check point Cause Check/Action
5. Propulsion Motor Propulsion motor inlet pressure is low. Measure propulsion motor inlet pressure.
If low, check and adjust multifunction valve
or replace it if necessary.
•
•
Propulsion circuit pressure is not held in
propulsion motor case.
If pressure in propulsion motor case is not
within allowable range, repair propulsion
motor or replace it if necessary.
Output of propulsion motor decreases and
number of revolutions decreases due to
internal leakage of propulsion motor.
Measure drain quantity from propulsion
motor.
If drain quantity is larger than standard
value, repair propulsion motor or replace it
if necessary.
•
•
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 speed cannot be switched
Check point Cause Check/Action
1. Speed Change
Solenoid Valve
Machine speed does not change because
spool of speed change solenoid valve does
not change.
Repair speed change solenoid valve or
replace it if necessary.
2. Propulsion Motor
Swash Plate
Stroke Cylinder
Faulty propulsion motor swash plate stroke
cylinder.
Repair propulsion motor or replace it if
necessary.
3-2-5. 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. Servo Cylinder Faulty servo cylinder or faulty pump swash
plate setting.
Repair propulsion pump or replace it if
necessary.