Water Addition

Some batteries have removable vent caps and may occasionally require the addition of water. If the electrolyte level is below the level indicator in any cell, add enough water to bring the level up to the indicator. In batteries without a level indicator, maintain electrolyte level at 6.3 to 12.7 mm (0.25 to 0.50 inch) above the plates. Never add electrolyte ("battery acid") to the battery. This could shorten the life of the battery.