Burnin' up '55 Pontiac....

[Kojack]

Hey folks... had a question for you electrical guys. My buddy was driving the other night, and it noticed this "weird sound" he thought was coming from the alternator when he was driving, but it was quick and he didn't make too much a note of it. It parks the car with no worries. Next day, his girlfriend is out doing laundry and she runs in the house ans says the goddamn car is smoking. We run outside, and the tailights and headlights are on, flickering back and forth. Looked like the damn car was posessed. He opens the door and smoke pours out... it filled the whole car up with it. He rushed under the hood, and undid the battery cable, and thankfully that put an end to it.

Does anyone have the SLIGHTEST clue what happend there? A lot of wiring was cooked to shit... the wire to thge battery gauge, ignition wiring, the wire to the alternator he installed, and a few other things. He said when he opened it, the alternator was burning up... it looks like it somehow started to get red hot, as the radiator hose looks a little singed and there is this greasy oil all over the alternator. Anyone ever heard of something like this before? The car is all stock, other then the chrome alternator... thanks for any help. Really baffling me.

[Rude Dude]

Sounds like the regulating diode gave out in alternator causes over amps in charging circuit. I would check all wiring now becuase it proably melted alot of insulators covering wire. may need to replace wire harness

[yorgatron]

ya know,folks go on and on about how "high maintenance" generators are,but i never run into problems like this.my guess is a dead short somewhere,probably the hot lead coming out the back of the alt. i've seen homemade brackets on older engines that put that terminal way too close to the block/exhaust too many times-george

[Kojack]

So you think something shorted out from the heat, being too close to the motor? The bracket is homemade, and resting pretty much on top of the motor, to the side...

[Rude Dude]

To prevent this try using an inline fuse out of alternator a least 20 amp breaker

[Rude Dude]

The diode proably just broke down look at all the new cars they have the alt lead fused.

[tommy]

I had the same thing happen to me. The alternator shorted out inside the case. The 10 ga wire from the battery to the alternator was a direct path to ground. Instant smoke. I ran an ampmeter so the cabin filled up with smoke. If the wire was bundled with the rest, you probably need a new harness.

Since then I always put a fuseable link in the line. It won't help you now but it may latter. It only has to happen once. I was driving when mine went up. I burn the shit out off my hand yanking wires untill it broke.

Yorgie, I put a fuseable link in my 12v generator circuit too! http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif

[Cadillacin Marcus]

It could just be old wiring, Period! Like my old 55 Plymouth,it did the same thing.. re-wire it and be safe and happy!

[whodaky]

Had the alt off my deuce many years ago. Next day took her out for a run came back parked it in the driveway. Came out a few minutes later and that coupe was starting to smoke. When I had put the alt back on had left of the insulating wire of the main wire into the alt, that short dirve was enough to make a good ground to earth. Burnt a wire right out through the loom, replaced the wire added the insulating washer and she has been right ever since.May not be your problems, but it was a lesson learnt for me that day.

[kyle paul]

i think rude dude has it right .a few monthes ago that happened to me .my voltage reg never shut off after i parked it and and it just keep chargen and my harness burned up .on my car the wires for the headlights and gen. lights go on the same plug so it burned them all up.