Section IX. MAINTENANCE OF THE ELECTRICAL SYSTEM

Section IX. MAINTENANCE OF THE ELECTRICAL SYSTEM

setting: (1) Battery is being overcharged, (2) battery

2-30. General

remains undercharged.

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

follows :

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

2-31. Alternator

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

strap.

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.

2-31