jcb JS130, Service Manual

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95 - 2
Section E Hydraulics
9803/6410
Section E
95 - 2
Issue 1
Slew Motor
Fault Finding (cont’d)
Table 2.
No. Part Inspected Repair
a Wear of the sliding surface of balance plate 21 . Repair or renew the part
b Damage to sliding surface of cam plate 6 . Repair the part or renew the motor.
c Damage to sliding surface of the piston assemblies 8 . Repair the part or renew the motor.
d External wear to the piston assemblies 8 . Repair the part or renew the motor.
e Wear to piston bores in cylinder assembly 24 . Renew the motor.
f Damage to Teflon ring 19 or ‘O’-rings 52 . Renew the part.
Symptom Cause External Inspection Countermeasure Repair
Wear or seizure of the Open motor inlet and High possibility of Inspect the parts and
motor sliding surfaces. outlet ports and apply 20 internal damage to the bearing according to
kgf/cm
2
(284 lbf/in
2
) pilot motor if the supply shaft Table 2 a-e and renew
pressure to the brake does not rotate smoothly any defective parts.
release port.Try to rotate when this torque is
the shaft with a torque of applied. Dismantle and
approx. 39.32 Nm inspect.
(29 lbf ft).
Relief valve in the circuit Measure relief pressure. Reset to the prescribed
is not set correctly. setting.
Internal damage to the Check if any metallic High possibility of Repair or renew
motor. matter is deposited in the internal damage to the damaged parts. Renew
motor drain oil or drain motor if metallic matter the motor assembly.
filter. is discovered.
Dismantle and inspect.
Large amount of air Check the oil in the tank Thoroughly bleed the air.
mixed in the oil. and motor casing.
Loosening of bolts or Check if the piping Tighten to the specified
pipes connections, attachment torque.
mounting bolts, motor
attachment bolts or other
bolts are loose.
O-ring is damaged Renew O-rings.
Seal face is damaged. Repair seal face or
renew.
Bolts are loose. Check the bolt tightness. Tighten the bolts to the
correct torque.
Insuf
ficient tor
que
Abnormal noise
Oil leakage fr
om
mating surfaces