Question Help needed... Boiling battery!

[VinceJE]

What would be the prime suspect causing this? Can it just be an internal short in the battery? Over charging? Short in the cables?
The truck has a single alternator system.

Here's what happened...

I had driven it for about 300 miles today with several stops. Never had any issues cranking or other electrical symptoms. I started smelling something in that cab that was sickening about 10 miles from home. I started checking around to find the source of the smell & found the right (passenger side) battery was hissing, steaming, and very hot. I put on the safety goggles & gloves and carefully pulled the fill caps and I could see the fluid in the batt simmering at a fast pace. I let it sit for a while and the boiling did not slow. I took a big chance and carefully removed the cables out of fear it was going to blow. The boiling slowed quickly and completely stopped within a minute.

The other side (left/driver side) battery was not boiling and was not hot. After all this the left side tested 11.78v & the right side tested 10.45v. I'm guessing they were both obviously drained a bit from the ordeal. The right batt is 18 mos. old. The left (the one boiling) batt is 6 mos. old. Both are Duralast Gold from AutoZone. I have had very good luck with these batteries over the years. I currently have 4 other vehicles with them and 2 are 6 yrs old and still good, so I don;t want to get into a who's battery is best debate. I just need to know if the symptoms I've described can get me pointed in a direction to get it fixed.

On one hand, it seems like it could be a short somewhere or overcharging, but then I would think that both batts would have similar symptoms.??

 

[Smoky]

I wondering if the fact that the batteries are not the same age may make a difference. The Battery that was in place of your newest battery would have been much older than the first new one you replaced. As I understand it you should replace batteries in pairs.

Then again it should like a short or something was overcharging the boiling battery.

Just my $.02 worth.

 

[VinceJE]

I did replace them as a pair originally, but the driver side got weak during the unusually cold winter we had here, found it had a dead cell, and got it replaced. (First Duralost Gold I've to ever have exchanged prematurely.) That's why their not the same age. I figured less than a year apart in age shouldn't be that big of a deal.

I topped off the batts with distilled water this morning. Checked the alt with both batts & then with each batt independently. Charging voltage never went above 13.1v, so I don't think I have an overcharging situation. I took both batts out and put them on a 25A charger. The Rt side batt started simmering within a minute. The Lt side batt never did. So it sure looks like that batt has some kind of internal short. I'm gonna take it to AZ to have them tested & replaced.

Should I be looking for anything else at this point?

 

[DaveBen]

Take it back. It should settle down after a while, when you put it on a charger.

Dave

 

[VinceJE]

So I took both batteries to AZ & had them tested. They found the one that was boiling to be bad & replaced it free of charge. The other battery was fine. I noticed the starter spinning much better after installing them, so I think that problem is solved. Now I have a new question... maybe 2 questions...

First... is it unusual for the battery posts to get hot after running for 30 minutes? Really hot? like I can't keep a finger on them for more than 5 or 10 seconds hot? I compared it with my car (Taurus) and it's batt posts were hot too, so maybe this is "normal"??

Second... some time back I posted a question about am intermittent problem with the instrument gauges. They would occasionally drop to zero and then peg and then go back to normal. Kind of like they do when you first turn the ignition key. Everything stays running smooth. Just the gauges cycle. Well... it happened again today after thousands of miles without happening. This time I noticed the batt light came on & went off when it happened. (No other warning lights) It's happened 4 or 5 times times today commuting to/from the office. This is why I was under the hood again checking the batteries in the first place. I going to resurrect the old thread to update what I've done on that issue so far.

 

[DaveBen]

You have a charging problem. Your battery posts should NOT got hot. I am guessing that your alternator regulator is not doing it's job, sometimes at least. This is tied to your dash problem, but I am not sure how or why. My guess is the alternator is over-charging and this causes Hot posts and funny dash problems. Any one else have a bright idea??

Dave

 

[W4RLR]

Bad battery or bad clamps. I had the same problem with the gauges, along with low voltage when cold, it went away when I replaced the original Motorcraft batteries with new Motorcraft batteries.

 

[VinceJE]

Well... So I took it to AZ & O'reilly this evening. Both places tested both batts (isolated from each other of course) and the alternator. It passed tests at both places. It's definitely not overcharging... if anything it's a little undercharging at 13.8v. The batts were fully charged, so it's not so low that they are getting strained while running. She spins fast & starts quick consistently, so I tend to believe the batts are holding good. The alt only has about 25k miles on it, but I think I should get some better testing done than the yayhoos do at my part houses.

The real sad part of it is that my wife is already shopping for a GMC/Chevy gasser at this point. We have a high mileage '02 GMC and haven't had any issues compared to this 6.0. Man I hate to admit this, but I just cannot afford all the gremlins we've had with thing that come & go without good explanation. And it really sux that I haven't found a PSD shop i the area that I have any confidence in. We may miss our first fishing tourney in 2 years this weekend because we just don't have much confidence we can make the trip without fear of breaking down. OK... enough of my whining, but I am really feeling disappointed in this truck overall and it makes me sick that it might be the first vehicle I've gotten rid of for that reason. I just have never had any vehicle so riddled. Dang it !!!

 

[4x4grey88]

I had to replace my batteries after only two years, good thing was that they were still under warranty.

 

[bismic1]

Alternators can have intermittant problems, so keep an eye on it.

Especially if you buy autozone alternators and batteries. They have great return warranties, but it is not uncommon to find yourself using the warranty!

You may have had many other issues - who knows, but it seems crazy to lose faith in the 6.0L and Ford's products specifically ...... based solely on a battery issue. That can happen w/ any engine make / model / etc.