to the shaft. The blade will vibrate above
(6) Remove washer (22) from shaft of armature
the short circuit if one is present. If an
external examination discloses nothing to
(7) Pull drive housing with armature from housing.
cause a short circuit, such as foreign
(8) Unscrew brush holder screws (18) and remove
material between the bars of the
commutator, install a new starting motor.
(9) Remove brush holder pivot pins (24) and spring
4. Check armature for grounding by placing
(25) from housing.
(10) Remove screws (9 and 30) lockwashers (8 and
one test prod on the end of the
31) that secure sleeve bearing (7) to drive
commutator and the other test prod on the
laminated core or shaft. If the test lamp
(11) Remove lever nut (36) and remove bolt (1) from
lights, a ground is present and the starting
motor should be replaced.
(12) Remove drive assembly lever (5) with plunger
(c) Field coils. Using 110- volt test lamp, check
(10) from housing.
for grounds between field coils and housing.
(13) Remove pin (6) that connects drive lever and
Place one test prod on housing and one test
plunger and separate plunger from lever.
prod on field lead. If circuit is grounded, light
(14) Remove thrust collar (3) from drive end of
will light. Then re-place starting motor.
(d) Drive assembly. Check to see that over-
(15) Remove retainer ring (34) that secures pinion
running clutch does not slip in forward motion.
stop collar (4) to armature shaft and remove
Check for broken spring and worn or burned
drive gear. If defects are found, replace drive
(16) Slide drive assembly (33) from shaft.
(17) Remove sleeve bearing (39) from drive housing
d. Assembly. Reverse procedures in b above. Coat
splines of drive assembly with OE oil.
c. Cleaning and Inspection.
e. Installation. Refer to TM 10-3930-222-20.
(1) Using air hose or clean cloths, remove dirt and
grease before proceeding with inspection of
a. Removal and Installation. Refer to TM 10-3930-
Caution: Do not wash armature,
field coils, or drive assembly In SD.
(2) Make the following tests:
(1) Unscrew and remove bolts (26, fig. 24) that
(a) Brushes. If brushes are worn to less than 1/2
secure commutator end frame (24) and drive
their original length, replace brushes.
end frame (7) to housing (15).
(2) Separate commutator end frame (24) from
1. If the commutator is worn, dirty, or out-of-
(3) Remove drive end frame (7) with armature (14)
round, turn the commutator in a lathe.
Sand the commutator lightly with No. 00
(4) Remove screws (21 and 27) and washers (20
sandpaper to remove any burs.
and 28) from brush holders and remove brushes
2. Check all wiring and connections. Use
rosin flux on any soldered connections
(5) Remove brush holder springs from brush
that are made.
3. Check armature for short circuits by the
(6) Pull armature (14) from drive end frame and
use of a growler. Revolve armature in a
growler with a steel strip such as a
hacksaw blade held over the core parallel