9
13
TM 9-4940-568-34
5-146
5-23. STARTER MOTOR REPAIR (CONT).
(2)
Check armature assembly (13) as follows
for shorts, opens or grounds.
(a)
Rotate armature in a growler holding
a steel strip such as a hacksaw blade
against the armature. If a short circuit
is present, the steel strip will vibrate
in that area.
(b)
Check the armature for grounds.
There shall be no continuity between
the armature shaft and any point on
the commutator.
(c)
Check for opens by visually
inspecting the points where the
armature conductors join the
commutator. A poor connection often
will be indicated by signs of arcing or
burning of the commutator.
(d)
Replace armatures which are shorted,
grounded or show evidence of opens.
(3)
Check frame and field assembly (9) for
grounds or opens, as follows:
(a)
Check that there is continuity (no
opens) between the field terminal that
connects to the solenoid, and the
connection points for insulated
brushes on the field coil straps.
(b)
Check that there is no continuity (no
grounds) between the frame and the
field terminal that connects to the
solenoid.
(c)
Replace frame and field assemblies
that have grounds or opens.
