How to Service Lead Acid Batteries
- 1). Remove the lead-acid battery from the vehicle, if necessary. A wrench set or small adjustable wrench is needed to remove the cable clamps from the battery. Disconnect the negative cable clamp first, followed by the positive. Once the battery has been fully disconnected, lift it out of the vehicle. Place the battery in a well-ventilated area for further servicing.
- 2). Sprinkle baking soda on top of the battery and over its posts. Add a small amount of water, just enough to turn the baking soda into a thick paste. Scrub the posts with a wire brush or terminal cleaning brush. Remove all corrosion from the posts. Remove any grime from the top, bottom and sides of the battery with an old rag. Rinse the entire lead-acid battery with fresh water once all the dirt and corrosion have been removed. Allow the battery to dry.
- 3). Check the water level in the lead-acid battery. Remove the caps found on top of the battery with a screwdriver. After the caps are removed, you will see a series a small plates within the battery. If the water level is below these plates, you will need to add fluid. Add enough distilled water to cover the plates. Do not add tap water, as the minerals in tap water may lead to corrosion problems.
- 4). Check the state of charge in the lead-acid battery with a digital voltmeter. Attach the voltmeter's positive and negative clips or leads to the matching posts on the battery. A fully charged 12-volt lead-acid battery should show a charge of roughly 12.6 volts. If the voltmeter displays a charge less than 12.6V, recharge the battery.
- 5). Recharge the lead-acid battery. Connect the battery to an automatic battery charger. Ensure the positive and negative clips/clamps on the charger are securely attached to the matching posts on the battery. Plug the charger in and allow the battery to fully recharge. The time necessary to fully charge a lead-acid battery will depend on the level of discharged. A full charge may take up to 14 hours. An automatic charger will shut down after the battery is fully recharged. Check the water level in the battery once again and add distilled water, if necessary.
- 6). Clean the cable clamps on the vehicle with the wire brush, water and baking soda. Also clean the battery compartment and any brackets used to hold the battery in place.
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