EP Equipment LIST JX0, Service Manual

Page: 88 / 206

75
REV. 07/2019
HYDRAULIC SYSTEM
7
7.3.2 Faults and Causes
7.3 Pump Motor
7.3.1 Removal and Installation
Removal
-
-
-
Remove the pump and motor assembly;
Remove the 2 long screws (1) on the motor
end cover, and remove the pump motor (2)
from the valve block (3);
If you need to replace carbon brush (4). Re-
move motor end cover, replace the carbon
brush on the holder.
-
-
After replacing the motor or carbon brush,
conduction test must be carried out to the
motor (see Section 7.3.3).
After replacing carbon brush, running opera-
tion must be carried out to the carbon brush:
By running the motor with repeated lifting,
letting the carbon brush to be fully running,
making its surface smooth to fit the rotor.
When installing the pump motor, make sure the
shaft and the coupling on motor rotor are mated
in place. (Rotate the motor around to make the
end surface of motor be in full contact with valve
block).
CAUTION
Due to magnetic force, the rotor and the stator
may pull each other, therefore, when disman-
tling motor rotor, do not hold your hand between
the rotor and the stator to avoid pinch hazard!
WARNING
- Install according to the reverse order of rem-
oval.
When replacing the carbon brush, replace the
complete set of carbon brushes.
CAUTION
Installation
Adjustment
1
Fault Motor does not rotate
Cause
a. Negative electrode cable
broken;
b. Motor positive and negative
electrode with loose terminals;
c. Armature winding with broken
circuits;
d. Motor bearing damaged and
blocked;
e. Serious wearing of carbon
brush.
2
Fault Motor speed is turning slow
Cause
a. Insufficient voltage of battery;
b. Carbon brush worn or carbon
brush spring pressure
decreases;
c. Bearing wear or lack of
lubricating oil;
d. Armature winding has short
circuit elements;
e. Carbon brush winding grounded.
3
Fault Motor sometimes can start,
sometimes cannot
Cause
a. Motor positive and negative
electrode with loose terminals
and poor connection;
b. Carbon brush wear and tear;
c. Armature winding has circuit
broken unit.