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Positive battery terminal turns black


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Anybody's guess?

 

The pos terminal on my battery turns a greasy black within 24 hours of being cleaned with a wire terminal brush. This happens whether or not it is connected in the car or in my house. I've never seen this happen.

 

Battery holds 12.4 volts at 70% charge; water is full.

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black sounds like H2SO4 leaking-does it smell or burn your skin? a good battery holds 14.3 or so volts I think. How old?

 

I thought I smelled a hint of rotten egg; not sure about the burn as I did not touch the stuff. Battery is less than a year old. How many days will a good battery hold 14.3 volts? What is H2S04????

 

Just googled it: Sulfuric Acid. Does this pose a danger to the car/electrical system? Probably best to replace the battery at this point.

 

Thanks

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yep if you smelled eggs that is the key signal of sulfur present. on a side note if anyone is looking to protect their battery terminals from corrosion and to guarantee good connection, vasoline is a great coating to keep the battery connections clean and corrosion free. i have used this for all my life and it keeps things to a squeeky good contact.

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yep if you smelled eggs that is the key signal of sulfur present. on a side note if anyone is looking to protect their battery terminals from corrosion and to guarantee good connection, vasoline is a great coating to keep the battery connections clean and corrosion free. i have used this for all my life and it keeps things to a squeeky good contact.

 

ah, that's probably neater than the red spray c**p I'v used. thanks.

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Also if leaking the gas is HIGHLY explosive. Had a battery years ago that had a crack in the top. One day I removed and reinstalled the pos cable. Got that little spark you always get and the battery literally exploded in my face. Only reason I am not blind today is the sunglasses I was wearing saved my eyes.

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i had a battery explode in my face serviceing a u-haul truck. i was popping the cap off and grounded my tool on the frame. i was not wearing safety glasses but i was lucky to escape with my vision. i go inside to proclaim that a battery exploded in my face, and the girl at the counter's response was "would you go pull up this truck for me"

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Charging a frozen battery also a big no-no. Recall about 40 years ago a cousin had this homemade battery charger. Just a generator powered off the motor on a compressor. No voltage regulator either. As he was connected the battery to the charger I voiced the opinion this was probably not a good idea and why not just give the battery time to thaw? He connected the battery and I headed for the door. Didn't make it. Battery went off like a bomb.

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Years back, my Mom had a '73 Montego. Nearest I can figure is the voltage regulator failed, over-charging battery. She stopped at a gas station for some gas. Upon the attempted re-start of the engine, the battery exploded. Mangled hood, fender, headlights just plain gone, and a few pairs of soiled undies.

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