jcb JS130, Service Manual

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91 - 2
Section E Hydraulics
9803/6410
Section E
91 - 2
Issue 1
Slew Motor
Maintenance Specifications
Item Inspection and Maintenance Standards
The crescent-shaped ports in the balance plate, which are in sliding contact with
the end face of the cylinder assembly shaft, act to switch between high and low oil
pressure. Any damage to the sliding contact face will increase leakage, causing a
decrease in volumetric efficiency and an increase in slip.
Balance Plate 21 Any seizure of the sliding contact face causes a reduction in mechanical efficiency
and can lead to further damage.
If the grooves or marks depths are less than 0.03 mm (.001 in), the plate can be
corrected using fine emery cloth.
If the wear is greater than 0.03 mm (.001 in), the plate should be renewed. The
plate should be renewed if it shows any sign of seizure.
Correct any damage to the sliding contact face of the slipper feet by using fine
Piston assembly 8 slipper feet emery cloth.
Renew the motor if the depth of any slipper foot oil groove is less than 0.45 mm
(.018 in) or if the slipper foot surfaces are seriously damaged.
Piston assembly 8 pistons The external surfaces of the piston assemblies should be practically unworn. The
motor should be renewed if a piston assembly shows any sign of seizure.
Cylinder assembly 24 piston bores The piston bores should be practically unworn. The motor should be renewed if
the bores show any sign of seizure or are badly damaged.
HYDRAULIC MOTOR The bearings should be renewed if any slight damage is noticed on the contact
Taper roller bearing 3 surfaces of the rollers or needles.
Needle bearing 22 It is recommended that all bearings be renewed on reassembly of the motor
REDUCTION GEAR because bearings can be damaged when the motor is dismantled.
Self-aligning roller bearing 57
Roller Bearing 62
HYDRAULIC MOTOR Renew any oil seal if damage to the lip is apparent.
Oil seal 2 New seals must be used when reassembling the motor.
REDUCTION GEAR
Oil seal 61
HYDRAULIC MOTOR Renew any 'O'-ring that appears to be damaged.
O-rings 11 , 13 , 33 , 36 , 41 , 45 , 52 New 'O'-rings must be used when reassembling the motor.
HYDRAULIC MOTOR The back-up rings must be renewed when reassembling the motor.
Back-up ring 32 , 35 , 46
!
CAUTION
If the machine is operated at full load, before its initial
run-in procedure is complete, it may cause scuffing and
seizing which can adversely effect the service life of the
machine.
8-3-1-5
!
WARNING
Hydraulic Fluid
Fine jets of hydraulic fluid at high pressure can penetrate
the skin. Do not use your fingers to check for hydraulic
fluid leaks. Do not put your face close to suspected
leaks. Hold a piece of cardboard close to suspected
leaks and then inspect the cardboard for signs of
hydraulic fluid. If hydraulic fluid penetrates your skin, get
medical help immediately.
INT-3-1-10/1
!
WARNING
Hydraulic Pressure
Hydraulic fluid at system pressure can injure you. Before
disconnecting or connecting hydraulic hoses, stop the
engine and operate the controls to release pressure
trapped in the hoses. Make sure the engine cannot be
started while the hoses are open.
INT-3-1-11/1