Fault Finding
Table 1.
95 - 1
Section E
Hydraulics
9803/6020
Section E
95 - 1
Issue 1
Slew Motor
Symptom
Cause
External Inspection
Countermeasure
Repair
Internal damage to the
Measure the oil drain
High possibility of
Refer to Table 2.
motor.
volume.
damage to the sliding
surfaces if the supply
volume is approximately
equal to the drain
volume. Dismantle and
inspect.
Internal damage to the
Open the motor inlet and
High possibility of
Renew damaged parts
motor.
outlet ports and apply
internal damage to the
or renew the motor
40 kgf/cm
2
(569lbf/in
2
)
motor if the supply shaft
assembly.
pilot pressure to the
does not rotate smoothly
brake release port. Try
when this torque is
to rotate the shaft with
applied. Dismantle and
a torque of approx.
inspect.
24.40 Nm (18 lbf ft).
Relief valve in circuit not
Measure pressure.
Reset to the prescribed
set correctly.
setting.
Wear or damage to the
Measure the oil drain
Leakage is too high if the
Refer to table 2.
motor sliding surfaces or
volume.
oil drain volume exceeds
to the high-pressure seal.
5 l/min (1.1 gal/min).
Dismantle and inspect.
Oil hot and excessive
Measure the oil
Reduce the oil
Refer to table 2.
leakage in the motor.
temperature.
temperature.
Seizure of motor sliding
Check for any metallic
If metallic matter is
Repair or renew the
parts or circuit.
matter deposited in
discovered or the supply
damaged parts. Renew
motor drain oil or drain
shaft does not rotate
the motor assembly.
filter. Apply a 40 kgf/cm
2
smoothly when torque is
(569 lbf/in
2
) pilot pressure applied, there is a high
to the brake release port
possibility of internal
and try to rotate the shaft
damage to the motor.
with a torque of approx.
Dismantle and inspect.
24.40 Nm (18 lbf ft).
Damage or wear to oil
Renew the oil seals.
seal lip.
Damage or wear of the
Repair the problem or
shaft seal.
renew the motor
assembly.
Motor does not run
Excessive slip
Abnormal heating
Leakage fr
om oil seals
Summary of Contents for JS70
Page 65: ......
Page 99: ......
Page 189: ...Section E Section E Hydraulics 9803 6020 Issue 1 33 4 33 4 Control Valves Control Valve 291360...
