BOMBARDIER 1980 Shop Manual page 207

SECTION 04
SUB-SECTION 03, (ELECTRIC STARTER)
Test for ground circUit
In
the armature using growler
test probes. Check between armature core and the
commutator bars. If growler lamp turns on, bars are
grounded.
Commutator
bars
Test armature for shorted windings usmg a growler.
When the armature is rotated in the growler with a steel
strip held above
It,
the strip will vibrate over that area
of the armature which has short circuited.
Growler
Test the armature for open circuit
uSing
growler test
probes. Place one test probe on a commutator bar and
the other test probe on the neighboring bar. Repeat this
operation for all bars, moving one test probe at a time.
If the growler lamp does not turn on, the armature circuit
between these two (2) bars has an open CIrCUit. The
armature should be replaced or repaired; open circu'lts
most often occur at the commutator riser where coils
are soldered. (Burnt commutator bars are usually an
indication of an open-circuited armature call.)
(ELECTRIC STARTER). PAGE 4
Field windings and brushes
Test the field winding for open circuit uSIOg growler test
probes. Place one test probe on the negative brush and
the other test probe on the yoke. If growler lamp does
not turn on, the field w'lnding has an open-circuit. The
yoke has to be repaired or replaced.
Check the dynamic brake Winding for open CIrCUit by
placing one test probe on the positive brush and the other
probe on the negative brush.
If growler lamp does not turn on, the winding circuit is
open-circuit and the yoke has to be repaired or replaced.
Brush holder
Check the brush holder for Insulalion performance uSIOg
growler test probes. Place one test probe on the IOsulated
brush holder and the other test probe on the brush holder
plate. If the growler lamp turns on. the brush holder has
poor insulation and has to be repaired or replaced.
Check the brush spring tension With a spring scale. This
should be done by placing the brush holder Into position
in the armature with brushes resting on the commutator.
The tension reading should be made when the spring
has Just come off the brush.
The spring tension should be from 850.5-1162.3 grams
(30-41 oz).
Overrunning clutch
The pinion of the overrunnIOg clutch should turn smoothly
In the counter-clockwise direction, and should not s!ip
in a clockwise direction with the armature fixed. If it is
defective. replace.
Check the pIOlon teeth for wear and damage. If defective.
replace.