I have a 2 year old Advance Auto Autocraft Gold battery in my Scion TC that has started leaking from the vent caps. In two years it never had done it, and the other day when I did my weekly underhood inspection the whole battery top was moist with acid. I was worried my alternator was messed up and overcharging, but my father's Snap On alternator and battery tester showed it was charging at the proper level. I am assuming this is an indicator I should return the battery(before it leaves me stranded) since it has a 3 year free replacement, am I correct?
Bad Battery?
- Thread starter Robenstein
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I just replaced an Autocraft Gold in My Corolla that was 9 years old and it also developed moisture on the top of the battery overtime. Obviously it didn't hurt the longevity of that battery, and it probably would have gone longer, but I ditched it just in case because of it's age. I've had many batteries that develop moisture on top so I think it's somewhat normal.
I do know tightening of clamps and especially hold down brackets can be critical in that if you overtighten the heck out of them, you can distort the batter case enough to where the terminal post seals can fail and vent excessive moisture, to the point you start getting the white crust on them.
That's my
and if your battery is fully charged and shows spec CCA, I doubt Advance will honor the warranty. You can always try.
I do know tightening of clamps and especially hold down brackets can be critical in that if you overtighten the heck out of them, you can distort the batter case enough to where the terminal post seals can fail and vent excessive moisture, to the point you start getting the white crust on them.
That's my
Mine is coming through the vent caps and not the posts though. The posts were dry actually.
How do you know it was battery acid?
Did the battery test out OK?
Are any of the cells low?
I have never heard of a defect in the battery causing excessive venting of battery acid. But I am only a shadetree expert, not a real expert.
Did you test the charge rate at various RPMs?
Did the battery test out OK?
Are any of the cells low?
I have never heard of a defect in the battery causing excessive venting of battery acid. But I am only a shadetree expert, not a real expert.
Did you test the charge rate at various RPMs?
I have terminal cleaner with color changing acid detector. If it turns pink or red its acid, and it was all acid.
Yes the alternator checks out okay from idle to 5k rpm. The battery load tests okay now, but if it keeps leaking I can assume it will run dry before the remaining year is up on the free replacement. I can only top it off with distilled water so many times before it dilutes the electrolyte too much.
Yes the alternator checks out okay from idle to 5k rpm. The battery load tests okay now, but if it keeps leaking I can assume it will run dry before the remaining year is up on the free replacement. I can only top it off with distilled water so many times before it dilutes the electrolyte too much.
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It wont fail. I tested it on the car and it held a load and its voltage was good. Like I said though, it just started doing it. Two years and nothing till the last few days. I guess I will just have to keep an eye on it so it doesn't corrode anything and hope it doesn't leave me stranded on a cold day.
People always seem to check the charging system it idle.
When suspected of overcharging, testing at idle speed is the least likely time one will see the 14.4+ voltages which will cause aggressive bubbling and electrolyte loss.
If the battery had been discharged through stereo use or other methods, followed by a longer highway drive, the voltage regulator 'might' have allowed 14.XX long enough to cause aggressive bubbling and electrolyte loss. Not really a big deal. Do note starting batteries hate being discharged below 80%, and if forced to live around that level, will live a short life.
Short trip driving will not return the battery to 100%. I know many think the alternator is some magical free energy device which nearly instantly recharges batteries, but this is the old wives tale which should be locked up with the insane old wives in the looney bin as they mutter about shoes and how all men are pigs.
I certainly wouldn't assume all is well cause a well known tool maker's tester flashed a couple green lights and gave you the warm and fuzzies.
I also would not freak out because the battery pushed some electrolyte out the caps. I would however test the voltage on the battery terminals themselves with a digital multimeter at your highway cruising speed RPM.
I'd also make sure the firewall and engine grounds are clean and tight as well as any connections on the back of the alternator itself. Disconnect battery before fiddling with connections on back of alternator if you go that far.
Testing at idle does not reveal much
When suspected of overcharging, testing at idle speed is the least likely time one will see the 14.4+ voltages which will cause aggressive bubbling and electrolyte loss.
If the battery had been discharged through stereo use or other methods, followed by a longer highway drive, the voltage regulator 'might' have allowed 14.XX long enough to cause aggressive bubbling and electrolyte loss. Not really a big deal. Do note starting batteries hate being discharged below 80%, and if forced to live around that level, will live a short life.
Short trip driving will not return the battery to 100%. I know many think the alternator is some magical free energy device which nearly instantly recharges batteries, but this is the old wives tale which should be locked up with the insane old wives in the looney bin as they mutter about shoes and how all men are pigs.
I certainly wouldn't assume all is well cause a well known tool maker's tester flashed a couple green lights and gave you the warm and fuzzies.
I also would not freak out because the battery pushed some electrolyte out the caps. I would however test the voltage on the battery terminals themselves with a digital multimeter at your highway cruising speed RPM.
I'd also make sure the firewall and engine grounds are clean and tight as well as any connections on the back of the alternator itself. Disconnect battery before fiddling with connections on back of alternator if you go that far.
Testing at idle does not reveal much
I would not worry about it as long as the battery passes a load test. I would just keep it clean be sure to use an acid neutralizer and then rinse it well with water. An acid film will form on the top most wet cell batteries over time it is not a sign of failure unless it is leaking from a crack in the case just top it off with distilled water.
As I mentioned I tested at idle up to 5k rpm. I know that alternator output changes with rpm so I checked it across the normal RPM range it would see with me driving it normally and even aggressively. And this tool does not just flash a dummy light, it is a meter and has been very accurate over the past years for him. As far as discharge, that should not be the issue either. I dont do short trips, usually they are 25 miles or more.
I will keep an eye on it as mentioned before. Hopefully it does not continue. I emailed advance about it with all this info and testing to see if they will warranty it. When I worked at a parts store we had a battery come in that passed the tests, but leaked like a sieve when you moved around. It was not sealed tight and we warrantied it. But that was a different chain.
I will keep an eye on it as mentioned before. Hopefully it does not continue. I emailed advance about it with all this info and testing to see if they will warranty it. When I worked at a parts store we had a battery come in that passed the tests, but leaked like a sieve when you moved around. It was not sealed tight and we warrantied it. But that was a different chain.
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Between 13.8 and 14.2 is what the meter said as I adjusted the revs.
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JHZR2
Staff member
No way I'd want free battery acid and loose enough seals to have wholesale hydrogen evolution. I'd check water levels at minimum if I was going to keep the battery, but I'd probably give it the college try at replacement if and only if I can be 110% certain it wasn't caused by the vehicle.
Oh, I am going to try it the next time I am back up home. My dad's shop does brisk business with the store up there and has a good relationship with the manager. He was with me when I tested it on Thanksgiving and saw the charging system was working right.
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