Alternator fire! I need some HELP

[hooterville]

I have had problems with my charging system lately. The battery light had been on for a couple months. Finally, the engine drained the battery and then the next one. I took my alternator to a rebuild shop and he determined the voltage regulator went out. He replaced it and I reinstalled the alternator. Things worked fine for a couple days until the same thing started to happen. I had known that the pos battery terminal had been cracked, so I replaced it by cutting the old stock terminal off and attaching a new terminal. I figured it would be done but today the same thing happened. I pulled over to the side of the road and the car wouldn't start. I lifted the hood and I smelled a burning smell but I didn't find the source quite yet. The mechanic said that the alternator needs a rebuild.

So, I went to take the alternator out today and noticed that the small o-ring that connects the alternator to the battery had been charred. The rubber housing had been charred, the metal pieces are good and there wasn't any other appearant damage. My questions are: What happened? What can I do to fix this? Did I (possibly) damage any other component?

 

[Jr's Sho]

That kinda happened to me but my O-ring that goes over the alternator stud broke into two pieces. If I were you, I'd look into replacing the whole battery cable that goes to the alternator unless you can splice in another metal ring to fit over your stud. First get a good connection between your alternator and your battery before assuming your alternator has gone bad again. I'm not sure what happened but fix the apparent things first. Why your car won't start, I have no idea. Is it turning over at all? If you have NO power at all like no lights on inside, check your battery and all the connections, it could have fried your battery or the wires connected to it. If you can get it started and the alternator is found out to be bad again, get one from an autopart store that has a lifetime replacement, it will be cheaper in the long run. That is if the guy who rebuilt it didn't offer a warranty. Keep us posted on what you find out.

 

[naval-avi8or]

If your batt was bad or not fully charged then you fryed your new voltage reg. no if ands or buts.

 

[hooterville]

The battery is brand new. I will check tomorrow to see if my alternator is good. The O ring that connects to the screw post on the alternator is intact. The screw post is bent, so I will have to get that replaced.

 

[Mr Anonymous]

It's possible that your B+ lead (that black wire with the orange stripe that connects to the post on the back of the alt. via the ring lug) is grounded elsewhere between the alternator, starter, or power distribution box.

I actually had my lug break after replacing the alternator and ground itself to the block causing the B+ lead to melt and cause the insulation to catch fire.

There's actually a TSB addressing the problem with ATX battery harnesses (# 94-21-3). The problem is the way they came from the factory, the harness has no play in it and engine movement can pull on the ring lug on the back of the alternator, causing it to loosen, break, etc. The TSB includes a procedure to loosen it up, as well as the P/N for a revised harness. I can email you a .PDF of the TSB if you'd like.

If after checking your harness and verifying your battery is fully charged you still get the light, chances are the regulator has been fried. Did the shop who rebuilt it for you give you any type of warr/guarantee? Even if they didn't, you should try to get them to repair it for free.

Whatever ends up happening, make sure the battery is fully charged before installing a new/rebuilt alt. When one is bad, they usually ruin the other pretty quickly.

 

[SHOZ123]

Was the terminal at the back of the alternator tight? Sounds like it could have been loose. The cable also might have been corroded or frayed with broken wires at the terminal.

<small>[ September 27, 2002, 09:48 PM: Message edited by: SHOZ123 ]</small>