OPERATOR'S MANUAL MAINTENANCE

Section E - Hydraulics
Fault Finding
Slew Motor
E-238 E-238
9803/9880-3
Slew Motor
Table 4.
Symptom Cause External Inspection Countermeasure Repair
Motor does
not run
Internal damage to the
motor.
Measure the oil drain
volume.
High possibility of
damage to the sliding
surfaces if the supply
volume is approximately
equal to the drain volume.
Dismantle and inspect.
K Table 5. ( T E-239).
Internal damage to the
motor.
Open the motor inlet and
outlet ports and apply 20
kgf/cm
2
(284 lbf/in
2
) pilot
pressure to the brake
release port. Try to rotate
the shaft with a torque of
approx. 39 Nm (29 lbf ft).
High possibility of internal
damage to the motor if
the supply shaft does not
rotate smoothly when this
torque is applied.
Dismantle and inspect.
Renew damaged parts or
renew the motor
assembly.
Relief valve in circuit not
set correctly.
Measure pressure. Reset to the prescribed
setting.
Excessive
slip
Wear or damage to the
motor sliding surfaces or
to the high-pressure seal.
Measure the oil drain
volume.
Leakage is too high if the
oil drain volume exceeds
5 l/min (1.1 gal/min).
Dismantle and inspect.
K
Table 5. ( T E-239).
Oil hot and excessive
parts or circuit.
Measure the oil
temperature.
Reduce the oil
temperature.
K
Table 5. ( T E-239).
Abnormal
heating
Seizure of motor sliding
parts or circuit.
Check for any metallic
matter deposited in motor
drain oil or drain filter.
Apply a 30 kgf/cm
2
(427
lbf/in
2
) pilot pressure to
the brake release port
and try to rotate the shaft
with a torque of
approx.39 Nm (29 lbf ft).
If metallic matter is
discovered or the supply
shaft does not rotate
smoothly when torque is
applied, there is a high
possibility of internal
damage to the motor.
Dismantle and inspect.
Repair or renew the
damaged parts. Renew
the motor assembly.
Leakage
from oil
seals
Damage or wear to oil
seal lip.
Renew the oil seals.
Damage or wear of the
shaft seal.
Repair the problem or
renew the motor
assembly.
Abnormal pressure in the
casing.
Check the pressure in the
casing and measure the
drain volume.
Set the pressure in the
casing below 3 kg/cm
2
.
(43 lbf/in
2
) Dismantle and
inspect if drain volume is
excessive.
Renew the oil seal.
Repair or renew the
damaged parts. Renew
the motor assembly.