Drive Motor Inspection And Service; Drive Motor Reassembly - JLG 1932RS/6RS Service And Maintenance Manual

8. Remove the screws holding the Commutator End Head
(9) in place and remove the commutator end head from
the frame and field assembly. The Armature (2) will be
attached to the commutator end head.
9. Pull back the Brush Springs (4) in the commutator end
head, pull the brush back and rest the springs on the
side of the brush. The brushes should move freely within
the holders.
10. Use an arbor press or a bearing puller to remove the
armature from the commutator end head assembly.
11. Remove the Snap Ring (7) and Bearing (8) from the com-
mutator end head. Discard the bearing.

Drive Motor Inspection and Service

NOTE: Refer to Figure 3-25.
1. Carefully blow out any accumulated carbon dust and
dirt from the Commutator End Head (9) and the Frame &
Field Assembly (2) using clean, oil free, compressed air.
2. Replace Brushes (5) that are worn below their usable
length of 0.6 in (1.5 cm), show signs of uneven wear or
signs of overheating, such as discolored brush shunts
and brush springs. Brushes should always be replaced in
complete sets of four. Use identical replacement parts;
do not substitute brush grades as the brushes are
matched to the motor type and application to provide
the best service. Substituting brushes of the wrong
grade can cause premature commutator failure and
excessive brush wear.
3. Make sure the Brush Box Assembly (6) is tight on the
commutator end head. Replace brush box assemblies in
the commutator end head if they are physically dam-
aged or brush holders are loose on the brush plate.
4. Visually inspect the frame and field assembly for over-
heating or other signs of damage. Check all wiring to
ensure that the insulation is in good condition. Verify
that pole screws are torqued to 250 - 300 in-lb (28.2 -
33.9 Nm). Verify field resistance using a suitable ohmme-
ter per the appropriate motor specification. Verify that
the field is electrically isolated from the frame using a
dielectric tester. Replace as necessary.
5. Visually inspect the Armature Assembly (3) for signs of
overheating or physical damage. Visually inspect the
seal surface of the shaft for excessive wear. Check for
grounded circuits using a dielectric tester by applying
voltage between the commutator and the shaft. Visually
inspect the commutator for excessive wear and over-
heating. Replace as necessary.
6. Visually inspect the brake surfaces for excessive wear.
Replace Brake Assembly (11) if necessary.
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SECTION 3 - CHASSIS & SCISSOR ARMS
7. Visually inspect the Wire Harness (1) for frayed insula-
tion, loose terminals, or other damage. Replace as nec-
essary.

Drive Motor Reassembly

NOTE: Refer to Figure 3-25.
1. After inspection and servicing, reassemble the wiring in
the Commutator End Head (9) as originally found.
Ensure the wiring does not contact metal parts and that
it allows the brushes to move unrestricted in the hold-
ers. Motor terminals must be assembled as shown Fig-
ure 3-27. Torque bottom terminal nut to 110 - 140 in-lb
(12.4 - 15.8 Nm).
2. After the motor has been disassembled, it is recom-
mended that new bearings be installed because bear-
ings may have been damaged during removal. Although
the bearings may appear and feel good, the bearing
races could be "brinelled" (races or balls deformed) and
may exhibit noise and vibration problems or fail within a
relatively short period of service. Press a new bearing
into the commutator end head, pressing on the outer
race only. See Figure 3-26.. Replace the Retaining Ring
(7) in the retaining ring groove.
3. Press the Armature (3) commutator end into the com-
mutator end head and bearing assembly, carefully sup-
porting the inner-race of the bearing. See Figure 3-26.
4. Carefully release the Brush Springs (4) allowing the
Brushes (5) to contact the commutator. Make sure brush
shunts do not interfere with spring movement.
5. Assemble the commutator end head to the Frame &
Field Assembly (2) and tighten the screws to 120 - 140
in-lb (13.6 - 15.8 Nm). Make sure to align the field con-
nection with the notch in the commutator end head.
Seal wires where they exit from commutator end head
with the Grommet (10).
6. Place the Gasket Seal (12) in the bottom of the notch in
the commutator end head. Align wires from the Brake
Assembly (11) into the notch in the commutator end
head. Secure brake assembly to commutator end head
using three bolts.
7. Install Wire Harness (1) to motor by connecting the
brake connectors and securing the armature terminals
to the terminal studs. Crimp the field connection (red/
orange to orange and blue to blue) together and heat
shrink. Motor terminals must be assembled as shown in
Always secure the bottom nut with a wrench as you
tighten the top nut. Torque top nut to 90 - 110 in-lb
(10.2 - 12.4 Nm).
3-23