red top vented sulfuric acid out the bottom.
Thread Starter
Drifting
Joined: Sep 2002
Posts: 1,614
Likes: 7
From: South Florida
red top vented sulfuric acid out the bottom.
So, I drive from Miami to Orlando tonight. I get about 20 minutes from my destination when I start smelling sulfuric acid (rotten eggs). I've had trouble with my current red top not holding a charge and had it on the charger for the last 24 hours.
I roll down the windows and turn the AC off and keep the car moving to get airflow into the engine bay. I stop the car, jump out, open the hood, pull the battery, and threw it on the curb. (Fortunately I had the tools for the battery removal present. I had just put it back in the car.
The red top was "steaming" (probably acid) out the bottom. Acid was present in the battery tray. I poured coke on the acid to neutralized it, and then rinsed it all down with some bottled water. I'm glad I was holding my breath, and it was venting down. (I was cautious when opening the hood, and had a fire extenguisher present.
Why did the battery get so hot? The threads the battery cable bolt go into were slightly stripped. Is it possible there was some arcing? (I've also been troubleshooting a burnt alternator wire.) What are your thoughts of the battery venting out the bottom? Could this battery have caught fire or exploded?
Thanks
I roll down the windows and turn the AC off and keep the car moving to get airflow into the engine bay. I stop the car, jump out, open the hood, pull the battery, and threw it on the curb. (Fortunately I had the tools for the battery removal present. I had just put it back in the car.
The red top was "steaming" (probably acid) out the bottom. Acid was present in the battery tray. I poured coke on the acid to neutralized it, and then rinsed it all down with some bottled water. I'm glad I was holding my breath, and it was venting down. (I was cautious when opening the hood, and had a fire extenguisher present.
Why did the battery get so hot? The threads the battery cable bolt go into were slightly stripped. Is it possible there was some arcing? (I've also been troubleshooting a burnt alternator wire.) What are your thoughts of the battery venting out the bottom? Could this battery have caught fire or exploded?
Thanks
Tech Contributor
Joined: Dec 1999
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Wow!!! Either the battery is:
- Shorted inside due to a defect
-You over charged it and damaged it and its shorted.
- Alternator severely overcharged the battery (did you see any over voltage warnings on the DIC???)
You should get your warranty on the battery and have the charging system properly checked out. Is the alternator wire loose on the back of the alternator?? That can cause it to overheat.
Make sure the alternator wire on the starter solenoid is also clean and tight.
I would also remove the access panel in the passengers front wheel well and conduct a more detailed cleaning with baking soda and water or acid neutralizing spray foam.
BC
- Shorted inside due to a defect
-You over charged it and damaged it and its shorted.
- Alternator severely overcharged the battery (did you see any over voltage warnings on the DIC???)
You should get your warranty on the battery and have the charging system properly checked out. Is the alternator wire loose on the back of the alternator?? That can cause it to overheat.
Make sure the alternator wire on the starter solenoid is also clean and tight.
I would also remove the access panel in the passengers front wheel well and conduct a more detailed cleaning with baking soda and water or acid neutralizing spray foam.
BC
Team Owner
Joined: Mar 1999
Posts: 28,753
Likes: 9
From: San Jose/Bear Valley CA
CA Events Coordinator
Wow!!! Either the battery is:
- Shorted inside due to a defect
-You over charged it and damaged it and its shorted.
- Alternator severely overcharged the battery (did you see any over voltage warnings on the DIC???)
You should get your warranty on the battery and have the charging system properly checked out. Is the alternator wire loose on the back of the alternator?? That can cause it to overheat.
Make sure the alternator wire on the starter solenoid is also clean and tight.
I would also remove the access panel in the passengers front wheel well and conduct a more detailed cleaning with baking soda and water or acid neutralizing spray foam.
BC
- Shorted inside due to a defect
-You over charged it and damaged it and its shorted.
- Alternator severely overcharged the battery (did you see any over voltage warnings on the DIC???)
You should get your warranty on the battery and have the charging system properly checked out. Is the alternator wire loose on the back of the alternator?? That can cause it to overheat.
Make sure the alternator wire on the starter solenoid is also clean and tight.
I would also remove the access panel in the passengers front wheel well and conduct a more detailed cleaning with baking soda and water or acid neutralizing spray foam.
BC
(just messing with you bro..) 
Tech Contributor
Joined: Jan 2007
Posts: 19,475
Likes: 1,171
From: Dyer, IN
Wow!!! Either the battery is:
- Shorted inside due to a defect
-You over charged it and damaged it and its shorted.
- Alternator severely overcharged the battery (did you see any over voltage warnings on the DIC???)
You should get your warranty on the battery and have the charging system properly checked out. Is the alternator wire loose on the back of the alternator?? That can cause it to overheat.
Make sure the alternator wire on the starter solenoid is also clean and tight.
I would also remove the access panel in the passengers front wheel well and conduct a more detailed cleaning with baking soda and water or acid neutralizing spray foam.
BC
- Shorted inside due to a defect
-You over charged it and damaged it and its shorted.
- Alternator severely overcharged the battery (did you see any over voltage warnings on the DIC???)
You should get your warranty on the battery and have the charging system properly checked out. Is the alternator wire loose on the back of the alternator?? That can cause it to overheat.
Make sure the alternator wire on the starter solenoid is also clean and tight.
I would also remove the access panel in the passengers front wheel well and conduct a more detailed cleaning with baking soda and water or acid neutralizing spray foam.
BC
Yep, check out the PCM for sure !
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Thread Starter
Drifting
Joined: Sep 2002
Posts: 1,614
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From: South Florida
I got all the bells and whistles going off because of the door relays or whatever is in there. I am going to pull them apart and clean them like Bill recommended in another post...maybe mixed in with the reduced engine power warning, and the passenger door electronics not working was a voltage warning...but I don't remember seeing it.
Last edited by Smokin Joe; Feb 2, 2008 at 02:37 PM.
Thread Starter
Drifting
Joined: Sep 2002
Posts: 1,614
Likes: 7
From: South Florida
So I'm looking at a new alternator too, at gm parts direct. Why does it sell the voltage regulator separate, or in addition to, the alternator. I thought the alternator had an internal voltage regulator?
of course these things are over $250.
of course these things are over $250.
Team Owner
Joined: Mar 1999
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From: San Jose/Bear Valley CA
CA Events Coordinator
Racer
Joined: May 2006
Posts: 352
Likes: 42
It could have failed just because it was a defective battery. I once had an exide battery in my van BLOW UP! The top blew off it with a loud bang! I had just driven home from work and parked in the drive, turn it off and then realized I need to move back some so when I tried to start it back up, KABOOM! I think it had built up excess H2 from charging on the way home, then when I started it up the high currents caused an arc inside the battery. It made a real mess under the hood. I washed it all out for a long time with the hose and then put on some acid resistant gloves to remove the battery. Sure glad that wasn't in the vette but in the old van.
As others have mentioned, Coke is an acid, it has a pH of 2 which is VERY acidic. Good thing you had some water with you, baking soda would have been better but who carries that around?
Hope you can get it cleaned up and everything back to normal! Better put a volt meter on the new battery before you go anywhere...
DocOhm
As others have mentioned, Coke is an acid, it has a pH of 2 which is VERY acidic. Good thing you had some water with you, baking soda would have been better but who carries that around?
Hope you can get it cleaned up and everything back to normal! Better put a volt meter on the new battery before you go anywhere...
DocOhm
Le Mans Master
Joined: Aug 2004
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From: Southern New Jersey, The wet part at the bottom
St. Jude Donor '08-'09-'10
It's not right for me to try and diagnose an electrical prob on the other side of the Internet, but for you to cook the battery I'm going to go out on a limb and suggest a scenario. I've seen just this thing happen in the past and would guess that the battery was a victim in all this and NOT the cause. I'm thinking it isn't a voltage regulator prob either. I want to blame diode failure in the bridge or rectifier. Alternators produce Alternating Current (hence the name Alternator) then rectify it to Direct Current (12v DC) I'm guessing as a possibility the alternator was throwing unrectified AC to the battery, literally cooking it 
(and possibly the output wire from the alternator). Please post your findings. Any codes?
(and possibly the output wire from the alternator). Please post your findings. Any codes?
Team Owner
Joined: Jan 2004
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From: NJ
For the the high costs of these things I hear an awful lot of bad things about them. Seeing as how Delcos have solved the issues with leakage, why buy these batteries?
Last edited by Chevy Guy; Feb 9, 2008 at 09:13 PM.
Thread Starter
Drifting
Joined: Sep 2002
Posts: 1,614
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From: South Florida
So the battery is replaced with a new red top, and no problems yet. I'm going to pull codes and post them tomorrow. I am going to pull the computer and components out and check for acid damage from the original crap delco battery.
Remember, this battery wasn't leaking per se, but it was venting acid in gas form. I haven't gotten around to calling optima, but they'll pry say that it was overcharged. I can't find any evidence of that, yet.
I'll keep you posted on what I find. I pulled my door electrical connectors apart and they don't look coroded. Which is strange because I kept losing powere to the pass door electrical accessories. The fix was to pull the fuse and put it back in, which may indicate corrosion in the fuse block.
Remember, this battery wasn't leaking per se, but it was venting acid in gas form. I haven't gotten around to calling optima, but they'll pry say that it was overcharged. I can't find any evidence of that, yet.
I'll keep you posted on what I find. I pulled my door electrical connectors apart and they don't look coroded. Which is strange because I kept losing powere to the pass door electrical accessories. The fix was to pull the fuse and put it back in, which may indicate corrosion in the fuse block.
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The name is Mat, Battery Mat... 
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Thanks for posting that up.
One good thing about the AGM batteries is that they are normally leak proof. It would be good to know what Optima come back with on this one. Did the dealer come back with any problem on the charging system? Either way, battery or electrical system, that was a pretty unusual failure.
Hope the clean up goes OK.
One good thing about the AGM batteries is that they are normally leak proof. It would be good to know what Optima come back with on this one. Did the dealer come back with any problem on the charging system? Either way, battery or electrical system, that was a pretty unusual failure.
Hope the clean up goes OK.
Last edited by DeeGee; Feb 10, 2008 at 05:41 AM.