Figure 10D-2. Starting Motor Overcrank Protection
VOLTS
MIN. AMPS
MAX. AMPS
MIN RPM
MAX RPM
20
70
110
5500
9000
Table 10D-1. Starter Motor No Load Specifications
I n t e r p r e t i n g Results of Tests
4. Failure to operate with no current
draw indicates:
1. Rated current draw and no load speed
indicates normal condition of the crank
motor.
A. Open field circuit.
This can be
checked after disassembly by inspect-
2. Low free speed and high current draw
ing internal connections and tracing
indicates:
circuit with a test lamp.
A. T o o m u c h f r i c t i o n - t i g h t , d i r t y , o r
B. Open a r m a t u r e coils.
Inspect the
worn bearings, bent armature shaft
commutator for badly burned bars af-
or loose pole shoes allowing the arma-
ter disassembly.
ture to drag.
C. Broken
brush springs, worn
B. Shorted armature. This can be fur-
brushes, high insulation between the
ther checked on a growler after dis-
commutator bars or other causes
assembly.
which would prevent good contact be-
tween the brushes and commutator.
C. Grounded armature or fields. Check
further after disassembly.
5. Low no load speed and low current
draw indicates-High internal resistance
3. Failure to operate with high current
due to poor connections, defective leads,
draw indicates:
commutator
and
causes
listed
dirty
above.
A. A direct ground in the terminal or
fields .
6. High free speed and high current
draw indicates shorted fields. If shorted
B. "Frozen bearings (this should have
fields are suspected, replace the field
been determined by turning the arma-
coil assembly and check for improved
performance.
ture by hand).
Electrical
Components
