(7) Replace field insulation if it is broken or
rough, pitted, or worn, mount the armature
torn.
in a lathe.
Take light cuts until the
commutator
is
completely
cleaned.
Remove all burrs by holding No.
00
(8) Test the armature and field coil windings
sandpaper lightly against the commutator
(TM 5-764).
while the armature is turning on the lathe.
(9) Inspect all other parts for worn, damaged,
(5) Use a dial indicator to measure the
or defective condition. Replace or repair
commutator-out-of-round.
Repeat the
worn, damaged, or defective parts as
turning process until it is perfectly round
necessary.
and smooth.
51. Generator Assembly Reassembly and Installation
(6) Undercut the mica after turning the
commutator. The mica must be undercut to
a depth of 1/32 to 3/64 inch.
If no
the generator in the reverse order.
undercutter is available, use a three-
cornered file and a piece of hacksaw blade.
Note. Do not install the cover band assembly (1, fig.
Start the groove in the mica with the file
12B) or insert the brushes (4) in the brush holders until the
and undercut it with the hacksaw blade.
The mica must be cut lower than the
reassembled and installed.
commutator segments. Do not leave a thin
edge of mica between any two segments of
b. Installation.
the commutator.
20/2).
Section V. STARTING MOTOR ASSEMBLY
52. General
(3) Disassemble the remaining items of the
commutator end frame in the numerical
The engine starting motor is a -pole, 24volt, dc.-type.
When energized by the starter solenoid, the drive pinion
(4) Disassemble the brush and holder
of the starting motor engages with the ring gear on the
assembly in the numerical sequence as
flywheel and cranks the engine at the proper speed for
starting. When the engine starts, the drive of the starting
motor disengages the drive pinion from the ring gear on
the engine flywheel.
washers (2) and remove the assembled
motor drive housing, armature, and drive
53.
Starting
Motor
Assembly
Removal
and
assembly from the starter frame.
Disassembly
a. Removal.
Remove the starting motor and
separate the assembled armature (6) from
the assembled motor drive housing (3, fig.
b. Disassembly.
(7) Disassemble the remaining items in the
(1) Remove the bolts (1, fig. 13A) and washers
armature and drive assembly and the motor
(2) and remove the assembled end bell (8)
drive housing in the numerical sequence as
(2) Remove items (4 through 9, fig. 18A) in
(8) Disassemble the field coils, frame, and pole
numerical sequenced remove the brush
shoes in the numerical sequence as
and holder assembly from the end bell.
AGO 8456A
35