My battery went bad in my '89 about a month ago. Recently replaced the alternator, maybe 4 months ago. When the battery went bad, I went and bought a new one and replaced the negative cable because it was shot to hell. Ever since I did that, the factory ammeter has been riding on the charge side about 1 line or so. Didn't really think anything of it, the truck has been starting fine and all electrical accessories have been fine. I drove to my bosses yesterday and when I got there you could smell a rotten egg smell. Popped the hood, and the acid in the battery was hot, almost boiling and you could see where some of it was running down the side of the battery. I've never seen that before. Do ya'll think it's a battery problem, or a voltage regulator or alternator problem. I had to get in the big truck and leave so I haven't had a chance to investigate it anymore, just looking for some educated guesses. Sorry so long

 

it seems like a voltage regulator problem to me. your battery acid shouldn't be boiling for any reason. i don't know though if your VR is external or internal to the alternator. they used to be external years ago but i don't know what year they stopped.

 

I think it's internal, just weird how that ammeter started that right when I put the battery in. I thought maybe the battery had shorted out inside, but I talked to the guy who sold me the battery a lil' while ago and he seems to think it's the voltage regulator or a bad diode.

 

well my guess is that since you had a bad connection with that ground wire that you probably weren't producing full amperage. once you replaced the wire, the connection was restored on comes the amperage.

 

Maybe so, sounds like a good excuse to me, Thanks

 

Somebody on here was talkin about a switch on the bottom side of the battery tray that is supposed control the battery from over heating and shut off charging if it get's to hot. Past that I know nothing, just though I would mention it in case it jogs somebodies memory.

 

Well, I figured out why the battery was boiling. tested the system yesterday and it was charging at an amazing 17.2 volts with the headlights off and 17.8 with the headlights on. Put a new voltage regulator on it and got it to around 15.5 volts. NAPA is gonna replace the alternator for me because it apparently has some problems to. I think I'm gonna make them give me a battery too because I think it is fried.

 

i'd atleast try to get one out of them too. glad you're on the right track though.

 

no wonner it was so hot


I dont know if on yers there is the heat sensor under the battery but on the 2nd gens there is a temp sensor under the battery tray that adjusts the voltage regulator according to the temp........so I have read anyway

 

I doubt there is Whitmore, but I'll take a look at it later