- 1). Take the caps off the top of wet cell batteries and look at the water level in each cell. If the cell is full, the water will appear to bulge downward slightly. Check each cell and add distilled water to the cells that are low, then replace the caps.
- 2). Clip the red lead of the battery load tester to the positive post of the battery and the black lead of the tester to the negative post of the battery. This is to make sure the batteries are fully charged. A fully charged sealed wet cell battery should read 14.6 volts. A sealed battery should read 14.2 volts.
- 3). Clean and dry the top of the battery thoroughly. Remove the battery cables from the posts. Use a battery post brush to clean the battery posts by fitting the wire-brush-like end over the post, then twisting the handle back and forth to scrub any buildup from the post. Sprinkle baking soda on top of the battery to neutralize any acid that may be present, then wipe the top of the battery with a clean disposable shop towel. Coat the battery posts with petroleum jelly.
- 4). Charge the stored battery at least monthly to avoid battery damage. A "smart charger," one that shuts off when the appropriate voltage is reached, is best for this unless you want to watch the battery while it's charging. Even with a "smart" charger, it's best to check on the battery frequently while it's charging.
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