Section IX. MAINTENANCE OF THE ELECTRICAL SYSTEM
setting: (1) Battery is being overcharged, (2) battery
The electrical wiring diagram for the truck is shown in
b. Adjustments. Corrections should be made as
figure 1-3. The electrical system includes the Id-volt
negative ground battery, distributor, ignition coil,
(1) If the battery uses too much water at the
spark plugs, starter motor and starter motor solenoid,
"normal" setting, reduce the voltage setting approxi-
current and voltage regulator, horn circuit, lights
mately 0.3 volt and check for decreased battery water
sending units and gages, and wiring. The electrical
usage over a reasonable period. If necessary, repeat
gage, horn, and lighting circuits are protected by
the process until the battery remains charged with a
fuses. Fuses are located on the underside of the in-
minimum use of water.
strument panel near the ignition switch.
(2) If the battery is consistently undercharged
(evidenced by inability to crank the engine) at the
normal setting, increase the voltage setting 0.3 volts
a. Removal. Refer to figure 2-21 and remove the
and check for improved condition over a reasonable
alternator as follows :
service period. If necessary, repeat this process until
(1) Tag and disconnect wiring.
the battery remains charged with a minimum use of
(2) Remove bolt, washer, and nut in adjusting
water. The external adjustment type regulator has
positive stops on the adjusting mechanism that will
(3) Remove bolt and nut below alternator.
prohibit excessive high and low settings. To adjust
(4) Remove alternator.
the voltage regulator setting of the external adjust-
b. Installation. Reverse procedure in a above.
ment type regulator, remove the access plug from the
regulator. Then for an undercharged battery insert
2-32. Voltage Regulator
screwdriver into slot and turn clockwise one notch
a. Test. The desired voltage regulator setting is
(0.3 volt) to increase the setting. For an overcharged
one which keeps the battery in a satisfactory state of
battery, turn counterclockwise one notch (0.3 volt)
charge (3/4 charge or more) without causing excessive
to decrease setting. Reference figure 2-25. Check for
battery water usage.
an improved battery condition over a service period of
reasonable length. If necessary repeat the above pro-
Either of the two conditions may persistently exist
which indicate the need for adjusting the regulator
cedure for a higher or lower setting.