B
ELECTRICAL
Read all of SAFETY and this section before attempting any procedure. Pay particular attention to Notices, Cautions, Warnings and Dangers.
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Repair and Service Manual
653045
(+) probe on the positive (+) post of the battery.
Note the reading.
c. Attach the DC voltmeter across the regulator’s
red and black leads.
d. Start the engine and accelerate to governed
speed.
e. The meter should read higher than before start-
ing the engine. In a reasonable amount of time,
the reading should settle between 14 and 15
volts, indicating the regulator is functioning prop-
erly.
f.
If no increase over battery voltage is observed,
there is a malfunction in the charging circuit.
g. If the reading is
above
15 volts, check to assure
the wiring harness and generator field winding
(green lead) is not grounded. If it is not, replace
the regulator.
h. If the reading is
below
14 volts, disconnect the
regulator’s green field wire from the system har-
ness. Temporarily connect the green field wire to
ground. If the voltage rises above its prior read-
ing, replace the regulator.
i.
If the above procedures do not correct the prob-
lem, check for faults in the vehicles wiring har-
ness and/or generator.
INSPECTION
1.
Inspect the commutator for wear or damage.
2.
Inspect the brush assembly for wear and damage to
the brush holder insulators. Check the brushes for
length, approximately 11/16” (17 mm) or to the line
marked on the brush and signs of carbonization.
3.
Inspect the armature for distortion or broken wires.
4.
Inspect the field coil insulators and lead wire.
5.
Check the bearings for free rotation and lack of end
play on shaft. Replace if necessary.
Fig. 5 Starter/Generator
3
1
2
4
6
9
8
7
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