My Lawn Tractor Battery Won't Charge
- 1). Turn off the tractor ignition. Use a dry cloth to remove all dirt and oil from the battery. Locate the positive and negative leads connected to the battery terminals. Use an appropriate-sized wrench or screwdriver to disconnect the negative lead from the battery terminal. Disconnect the positive lead. Place both leads where they cannot fall back onto the battery terminals.
- 2). Use a wire brush to clean the battery terminals until they shine. Corrosion can severely hinder successful recharging. Wipe the battery clean of debris. Unless the battery is a sealed and low-maintenance model, remove all the dirt gathered around the vent caps.
- 3). Undo the vent caps on all the battery cells, unless the battery is a sealed model. Use a flashlight to look into each cell. If you can see the tops of the metal plates above the level of the liquid electrolyte, add battery water until the plates are covered. Refit the vent caps but do not tighten them.
- 4). Connect the battery to an appropriate battery charger and allow it to charge overnight. Switch off and then disconnect the battery charger and allow the battery to rest for 12 hours. Put on goggles and acid-resistant gloves, remove the vent caps and insert a battery hydrometer into each cell. A properly charged cell has a specific gravity of 1.265. No cells should vary from this by more than 0.005. If the cell-specific gravity is below this level, very carefully add battery acid to the cell, following the manufacturer's instructions, until the specific gravity is correct. Refit and tighten the vent caps.
- 5). Recharge the battery. If the battery previously had a low specific gravity but still fails to charge, it may be suffering from sulfation, a buildup of lead-sulfate crystals. Take it to a battery specialist who can offer advice, which might be to buy a new battery.
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