After doing a search on this site about white powder by a battery post, I came upon this from the FAQ:
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"It is the nature of a battery to eat away the post seal. When it does you get the white powder. Felt washers and grease do not keep the acid from eating the seal away. The white stuff is the end result of the seal failing and efforts to remove the white powder do not cure the problem."
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Does this mean that my battery needs to be replaced? It seems to start and run fine. The voltmeter in my car shows nominal voltage, although I'm running the original 21-year-old alternator and voltage regulator.

It's an Interstate battery, about four years old.
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Mike F - 1984 244 DL - 244,000 miles - Undergoing reconstructive surgery with POR-15

Calm down all it is is Corrosion. All batteries have some. Good old wire brush and clean it up. Than black spray paint it and it should be fine. The battery is fine.

While I'm not a battery expert, I would suggest that you start by cleaning the top of the battery and battery posts. Use baking soda and water to clean and neutralize. You may want to also remove the battery clamps from the posts and wire brush the posts and inside of the clamps. Note: there is a specific tool -- very inexpensive-- made for cleaning battery posts and clamps. When reinstalling the clamps do not overtighten down on the posts. Just secure firm so that you can't turn the clamp on the post once it's tightened down.

The battery felt washers seem to work on my cars; however, I also coat the battery posts and clamps with lithium grease. Some use other types of grease or petroleum jelly (vaseline).

So, first clean then after assembled coat the top of posts and outside of the clamps. This should help keep the posts from oxidizing (white powder).

You can also run some tests on the battery to check it's capability, but it sounds to me like it's probably ok, just a bit of oxidation from the lead in the post.


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dnvolvo '89 765T 200K - '91 245 100K