TM 5-3810-300-24 & P2
SPECIFIC GRAVITY TEST.
Specific gravity testing of the electrolyte determines the
state of charge of each battery cell. Perform specific
gravity check as follow:
1. Remove all vent caps from battery.
2. Using a hydrometer, check the specific gravity
reading of each battery cell.
3. Reinstall battery vent caps.
A SPECIFIC GRAVITY READING, IN ANY ONE
CELL, OF 1.250 OR LESS, INDICATES THAT
THE BATTERY REQUIRES CHARGING OR
Adding Water to Batteries.
The water in the battery electrolyte solution evaporates at high temperatures or with excessive charging rates, therefore it
may sometimes be necessary to add water to the battery. Add only clean, distilled water, as necessary, to bring the
electrolyte level to 3/4-inch above the plate separators avoid overfilling the battery.
The tops of the batteries, as well as the battery terminals and cable connectors, must be kept clean at all times. Clean the
battery as follows:
COVER ALL METAL AREAS OF CLEANING BRUSH WITH INSULATING TAPE PRIOR TO USE.
1. Tighten all vent caps and clean top of battery and terminals with a soft bristle brush dipped in an alkaline solution
(ammonia) or a solution of bicarbonate of soda and water.
2. After foaming action of cleaning solvent stops, flush top of battery with clean water.
3. Coat terminals and cable connectors with a light coat of petroleum jelly, or equivalent.