Battery

[brisyd]

How do I remove the white corrosive deposit on one of the terminals of my car battery? What causes this to happen please?

[dannydingbat]

Don't know what causes it but I use Vaseline and a clean rag. Stick some more Vaseline on the clean terminals to stop further deposits.

[dilligaf]

A drop of very hot water will remove it. After drying smear with Vaseline, this will prevent further corrosion.

[brisyd]

Thank you both for your suggestions. I have done the deed and it looks successful.

[Clanad]

If all you've done is to clean the corrosion from the outside of the terminal and its cable, you haven't really helped much. The corrosion is caused by the contact of dissimilar metals... copper and lead in this case. The corrosion can and does form between the battery post and the cable connection. It can disrupt the flow of electricity to start your car. Best practice is to take the cables from their terminals, dip the end of the cable in a container of water mixed with common bicarbonate of soda. Do the same with the terminal itself. Rinse well and brush with a steel wire brush made for this purpose and available at any DIY store. (Don't splash any of the mixture on your clothes!) Use the mixture to clean the terminal as well. Then coat the terminal with Vasoline or other thick lubricant and replace the cable. A word about connecting and disconnecting batteries. Always disconnect the ground (negative) or black cable first but when replacing always reconnect the hot (positive) or red cable first. A tip to help prevent cable corrosion in the future. Place a small drop of Vaseline on top of the battery near the terminals and stick a copper coin (ours is a penny) to the grease. The penny will draw the corrosion and helps greatly to reduce further corrosion of the terminals... zinc actually works better but is harder to find. Replace the coins when corroded.

Good luck!

[dilligaf]

If you follow the sound advice given by Clanad make sure that if you have a coded radio you have the correct code. The radio will go dead once you disconnect the battery and unless you have the correct code there are problems.

[UsAndStuff]

I thought good old coca-cola was good for cleaning battery terminals,
Also, would copper grease be better than vaseline, it's easy enough to get hold of, and it's conductive.