Battery Terminal Corrosion
The problem arises more often if you don’t use your tractor or riding mower regularly. When the engine is not running and the battery is sitting, the terminals oxidize at a faster rate. This means that you need to check the battery terminals more often for corrosion. Corrosion appears as a white, ashy deposit around one or both battery posts. Sometimes there is also a bit of color mixed in. These deposits are the result of one of several possible chemical exchanges involving vapors and the battery post.
How to Clean Battery Terminals
First of all, we recommend that you use skin and eye protection when performing this procedure. A combination tool – battery post brush and battery clamp brush, obtainable at any auto parts store, or online, comes in handy, although you can use a toothbrush and some soap-free steel wool. The combination tool generally comes in two designs, one employing wire brush elements and the other using two cutting blades and a reamer. Though old pros prefer the latter, either will work and either is suitable for occasional use. We prefer the brush-type terminal and clamp cleaning tool that has brushes for terminal-outside cleaning and clamp-inside cleaning. Here is a complete list of needed supplies:
- Plastic eye protector for your eyes
- Gloves (plastic, cloth, or leather)
- Pliers or locking pliers (vice grips)
- Toothbrush and soap-free steel wool or battery terminal/clamp cleaning combination tool
- Baking soda
- Clean, lint-free cloth
- Grease or petroleum jelly
- Remove the battery cables from the battery terminals by loosening the nut on each cable clamp. Once they are loose, always remove the cable clamp from the negative terminal first. It’s marked with a minus (-) sign, has a black lead wire, and sometimes is covered by a black boot. The positive terminal is marked with a plus (+) sign, has a red lead wire, and is usually covered by a red boot. Later, when replacing the cables, reverse the procedure, positive first and negative second. The cable may not come off easily. You will have to wiggle it and lift it upward until the clamp comes off the terminal post. Sometimes, especially if there is a lot of corrosion, you may need the assistance of pair of pliers. Be careful not to short any tools you use, including jumper cables, against the machine when they’re in contact with the battery.
- Examine the battery cables and clamps for excess wear or corrosion. Should damage appear extensive, replace the cables and clamps to avoid future problems.
- Check the battery case for cracks and the terminals for damage. If you find either, replace the battery.
- Secure the loose cables so that they don’t accidentally touch one another or flop back onto the terminals or against any metal surfaces on the machine.
- Prepare a solution of 1 tablespoon baking soda to 8 oz of water and pour on the top of the battery, the terminal posts, and the cable clamps to dissolve corrosion deposits. Scrub the terminal posts and cable clamps with a toothbrush.
- For particularly stubborn deposits, pour some baking soda directly onto the posts and/or clamps, dip a toothbrush in water, and scrub the baking soda into the terminal posts and/or cable clamps with the toothbrush.
- If the toothbrush isn’t doing the job, use a battery cleaning combination tool with brushes on it. Also shine up the insides of the cable clamps by using the clamp cleaner that usually comes attached to the terminal brush or use a plain, soap-free steel wool pad.
- Dry everything off with a clean, disposable, lint-free rag.
- Smear grease or petroleum jelly on the posts and clamps to slow down the formation of corrosive deposits. Cover all exposed metal surfaces on the battery posts, battery cables, and clamps.
- Replace the positive clamp (red) first and then replace the negative clamp (black). Tighten them down with the proper sized wrench.
- Replace the red rubber boot or plastic shield that covers the positive terminal and if applicable, the boot/shield for the negative terminal. The latter boot is not required and may not be supplied. If you don’t have a boot, you can buy one from your local auto parts store.
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