I replaced my original alternator about 3-4 months ago, with a bosch "premium" rebuilt. That one shorted out and stopped charging within the first month, after a whiff or two of hot electrical smell. I found a loose piece of solder inside, so probably a defect. Enter the second, also a Bosch "premium" rebuilt, as it was under warranty. Two months later, and now the voltage gauge on the dash was reading 12, less with the headlights or signals on. I decided to check under the hood, and

battery acid is leaking from the cap vents?! WTF is going on? I assume the regulator in the alternator is shot, which is overcharging the battery? These are internally regulated, am I right? Or, s there one on the left fender well somewhere? Thanks for any help.







It has new battery cables, and all the grounds were cleaned and reattached last year.

 

when replacing an alternator u should always replace the battery at the same time. same **** has happened to me

 

I think the only year that had a external regulator was 79 every thing newer will have the regulator inside..

Yeah I would try replacing the battery also.

 

The battery is fine, it lasted through two of those crap "premium" alternators. There's no reason to replace it if it's still holding a charge?,,,,BD

 

Thats messed up!! Bosch is spendy crap anyways, But two bosch premium alternaters in a row!!! well third time is a charm at least thats what the say. if you get another alternator and you have the same problem (IMO) I would say that its got to be somthing else.....



But what else could be the problem???



1. alternator....???

2. voltage regulater...???

3. battery...???

4. wiring...???



I think thats everything???????

 

After checking wiring ,I would get a multi meter and amp clamp, that will give you the true readings of what your alternator and battery are doing.I would also check to see the amp output capacity on your bosh alternator. I beleive most cars around 40 amps. Depending on how the armature is wound internally will determine the peak amp capacity,it should be stamped on the rear of the alternator. The other thing i would look at is the Amp hour capacity of your battery 550 cca...1000cca or cold cranking amps. A easy way to explain it is the larger the battery ,the more led inside and the less likely to boil. If you have the combination of a 550 ah battery with a 75 amp out put alternator the current spike when the regulator turns on could be the cause of your boiling battery.....I hope this helps ...Good luck

J

 

The only time it boiled the battery is the day it died. I looked under the hood the day before and nothing. I took a short trip(12 miles round trip) and the battery had boiled and the alternator was putting out nothing. I imagine it shorted internally like the first one, then started overcharging until it burned itself up. Been going fine on the Advance(worldwide) replacement since the day of this post. Running about 13.5(7) at idle. If this one dies prematurely I will start checking elsewhere, but for now there's no boiling or charging problems.,,,,BB

 

Yep that sounds like the regulator was stuck in the on position and boiled the battery and smoked the alternator. You might just have some bad luck... If the problem continues let us know and i will do my best to walk you through other testing to find help the source of the fault.

Happy holidays....J