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Battery cleaning

My battery has built up some gunk around the cables and such and I was wondering what is the best way to clean that gunk off.

A wire brush to get the big gunk off and then follow up with a solution of baking soda and water. You’ll note it starts fizzing.
Disconnect the battery before cleaning it, though.

What RemcoW said…

Also clean the cable connectors too.

Baking soda or baking powder is preferred. Some old-timers swear by Coca Cola, which actually works.

The problem with Coke…it’s it leaves a sticky residue.

Baking SODA (not powder ) and wash down with water.

WE poured Coke on the battery terminals of a van that would not engage after a band job at 2am.
It started right up…( rinsed it off with water later )

What is most important is to clean the mating surfaces between the battery and connector, not just the outside.
Remove the cable from the battery, clean the battery post and the inside of the clamp.

Instead of a wire brush, which will leave microscopic bits of steel in the terminals that will cause galvanic corrosion in the future, red Scotchbrite would be better. The green also works but it is not as aggressive as the red.

Following up on @circuitsmith’s good advice…if your cable ends are not factory formed but have bolts and a small plate which hold the cable to the connector, you may also want to disassemble them in order to clean the wire strands which make up the cable, likewise any smaller wires that attach to the connector. Your objective is to remove as much coating and deposits as possible, get the metal clean. Wearing safety glasses is a good idea for this.

Would a “hard” toothbrush work also?

I always boiled water with some baking soda in to neutralize the deposits. I never disconnected the battery but if you do, make sure you know what you are doing as far as radio codes and computer issues as discussed in other threads.

Would a "hard" toothbrush work also?

Sure does. Just use your mother in law’s toofbrush, when she visits.

Not married…:wink:

If one or both of your battery posts has repeated corrosion around it, then you likely have a “broken seal” around the post. This allow acid vapors to seep through the post seal and corrode your battery clamp.

After you’ve done all the cleaning recommended in previous replies, then apply battery paint (available from parts stores) to the area where the post meets the battery. Don’t paint over your previously cleaned post. Then apply a felt battery pad, which retards corrosion, and reapply your clamp. Some then repaint the completed assembly - I usually do.

Actually the crud isn’t around either cable, it’s on other parts of the battery, the terminal’s themselves have very little crud on them at all.