Sakai SV201-1, Руководство по ремонту

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9-050
TROUBLESHOOTING
3-2. Propulsion System
If a problem occurs in the propulsion systems such as the propulsion pump, propulsion motor and brakes,
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.
3-2-1. Machine moves neither forward nor backward 1/2
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. Bypass Valve Bypass valve is open. Close bypass valve.
3. F-R Lever Linkage F-R lever linkage is faulty. Check and adjust F-R lever linkage or
replace it if necessary.
4. Charge Circuit
Pressure
Propulsion pump does not discharge oil
because charge pressure is low.
Measure charge pressure.
If low, check and adjust charge relief valve
or replace it if necessary.
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•
Insufficient charge pump discharge. Repair charge pump or replace it if
necessary.
Charge pressure decreases due to internal
leakage of solenoid valve connecting oil
supply circuit with charge circuit.
Parking brake solenoid valve •
When solenoid is energized, check if oil
flows in return circuit to tank.
If oil is flowing, repair solenoid valve or
replace it if necessary.
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•
5. Hydraulic Oil Filter Charge pump flow is reduced due to
clogged filter.
Clean hydraulic oil filter or replace it if
necessary.
6. Propulsion Circuit
Pressure
Circuit does not obtain required pressure
because setting pressure of high pressure
relief is low.
Measure propulsion circuit pressure.
If low, inspect high pressure relief valve or
replace it if necessary.
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•
7. Propulsion Motor 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.
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.
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•
8. 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.
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•
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.
9. Parking Brake
Solenoid Valve
Brake remains applied because spool of
parking brake solenoid valve does not shift.
Repair parking brake solenoid valve or
replace it if necessary.
10. Brake Inlet
Pressure
Brake cannot be released because brake
inlet pressure is low.
Measure brake release pressure.
If low, repair or replace rear axle.
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