TM 5-3805-280-24-2
Engine Tune-Up and Break-In
CHECK ELECTRICAL SYSTEM
100
15
CAUTION: Battery gas can explode. Keep
sparks and flames away from batteries. Use a
flashlight to check battery electrolyte level.
Never check battery charge by placing a metal
object across the posts. Use a voltmeter or
hydrometer.
Always remove grounded (-) cable clamp from
battery first and replace it last, when
disconnecting and reconnecting battery.
1. Clean batteries and cables with damp cloth. If
corrosion is present, remove it and wash terminals with
a solution of ammonia or baking soda in water. Then
flush area with clean water.
2. Coat battery terminals and connectors with petroleum
jelly mixed with baking soda to retard corrosion.
3. Test batteries. If batteries are not near full charge, try
to find out why.
4. On low-maintenance batteries, check level of
electrolyte in each cell of each battery. Level should be
to bottom of filler neck.
If water is needed, use clean, mineral-free water. If
water must be added to batteries more often than
every 250 hours, alternator may be overcharging.
NOTE: Water cannot be added to maintenance-free
batteries.
5. If batteries appear to be either undercharged or
overcharged, check alternator and charging circuit.
Follow diagnosis and testing procedures outlined in
CTM77.
6. Check poly-vee belt wear. (See Group 30.)
7. Check operation of starting motor and gauges.
RG,100,JW7634 1921NOV971/1
13-478