Procedure For Other Batteries
If the battery is fully charged, check and, if necessary, top up the electrolyte using distilled or deionized water:- according to the manufacturer's instructions, or
- to any obvious level indicator, or
- ensure that the level is 6 - 8 mm (1/4 - 5/16 inch) above the top of the plates, while leaving air space between the electrolyte and the bottom of the filler plug thread.
Fully topping up the electrolyte level of a partially charged battery may lead to overflowing of electrolyte when the battery is subsequently fully charged.