- 1). Loosen and remove the battery vent caps. Check the electrolyte level for each cell. If any of the cells are completely dry (lacking electrolyte fluid altogether), add battery acid to the cell until the electrolyte level reaches the bottom of the “fill” line. Replace and tighten the vent caps on any cells that were filled with acid.
- 2). Fill each remaining cell with distilled water until the electrolyte level reaches the bottom of the fill line.
- 3). Replace and tighten the remaining battery vent caps.
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