How to Clean Battery Terminals
Greasy, dirty, corroded battery terminals (posts) are perhaps the leading cause of vehicles failing to start. This was always true and still is, although modern battery manufacturers now utilize threaded posts and anti-oxidation compounds to minimize the problem.
Our old cars don't have modern features. To complicate things further, we don't drive our collectible cars very often, so the battery terminals tend to oxidize even faster. If you want to prevent no-start or sudden shutdown situations in your car you must keep the battery terminals clean. Here's how-
First, you need to buy a battery post cleaning tool. These generally come in two different designs. One has stiff wire brush elements imbedded in a plastic holder and the other, older design, has two cutting blades and a reamer. We prefer the latter design because it doesn't wear out or need cleaning as frequently, and we think it does a more thorough job.
Remove your two battery cables and take a look at the posts. Notice anything? If not, look again! One post is a larger diameter than the other. This is one of those little-known facts about markings or colorings to guide placement of the cables.
Now look at the inner diameter of the cable connectors. Does the metal look shiny or dull, and is there any dirt or oxidation present? The answer is: probably, but we're going to clean them anyway.
Ready? Push the larger cutter end of the tool onto the positive post and start turning. It will begin to shave away a little of the lead post's material, much the way a wood plane shaves the surface of a board. Turn it a few times until the post is shiny and clean, then do the same to the other post, using the smaller cutter end of the tool.
Now you need to use the reamer to clean out the cable terminals. This is done much the same way as the posts, but you will find it takes a bit more force to push the reamer as it is turned. Keep working until the terminals are clean and shiny.
Now that all the components are cleaned, reassemble everything and tighten the nuts until the cables can't be moved on the battery posts. Feel free to add one of those "anti-oxidation" felt washers (found wherever batteries and tools are sold) or coat the terminals with petroleum jelly if it makes you feel better, but we prefer to leave everything as it is. Doing so makes it easier to see if things are getting oxidized again.