flaming alternator

[brdhrrs]

So I'm went to start my Tahoe today and it was stone dead. Thought that was really odd considering the battery is less than a month old but thinking it must have been the cold I had a buddy come boost me. Then bout an hour later I'm driving along and I get this knarley acrid smell bombing through my heater followed by a loud squelching noise. so i pull over just in time to see smoke pouring outta my hood. I immediately shut the vehicle off and opened my hood to see my alternator flaming this funky shades of green and melting the wiring harness thing plugged into the side of it. I grabbed a wrench and unhooked the battery while my girlfriend dumped snow on the fire. What a great afternoon!

My question now is what the hell do i do? I'm mechanically inclined sure but I've never had the belts off this thing before and I'm wondering how long/difficult of a job swapping that alternator is gonna be. Also if there is anything else is should be changing while I do this and finally why the hell did this happen in the first place? I'm guessing some sort of short but this is defiantly a first for me! Any advice would be appreciated while i now attempt to remedy this problem. Oh and P.S. I'm a student so "take er to the local chevy dealer!" would rank about the lowest in my advice column. THANKS AGAIN!

 

[sasquatch094]

its really not hard to get the belt and alternator off. to relieve tension off the belt, theres that tensioner pulley at the top in whichyoull need to turn it with a 3/8socket i believe or something. then like a couple bolts and unplug the wiring harness from the alternator.. but is that wire fried or what?

 

[txredneckmedic]

its a 13mm....and best to use a box wrench....just did it yesterday

 

[brdhrrs]

i went out and checked it and like you said it doesnt look to bad. now i just have to hunt down an alternator. looks like that harness is bigtime fried and the wire leading back to my positive battery post is burnt too. could that have been where the sort was? and has this happened to anyone before?

 

[95TwinTT]

That wire is supposed to incorporate a fuseable link. You should include a fuse when replacing that wire from the battery to the alternator.

 

[NYrr496]

Your girlfriend sounds like a keeper. My wife woulda ran away screaming while I dealt with the fire.

 

[treepete]

This is what we would call a "catastrophic" failure, where a high amp fuse would have saved the day. I learned that from a dude on this forum.
Maybe the hot from the battery was shorting on the alternator case, but, who really knows. GL and welcoem to the forum.

 

[95TwinTT]

i went out and checked it and like you said it doesnt look to bad. now i just have to hunt down an alternator. looks like that harness is bigtime fried and the wire leading back to my positive battery post is burnt too. could that have been where the sort was? and has this happened to anyone before?

Is there a chance that you accidentally hooked up the jumper cables backwards?

There should have been two wires hooked to the alternator. The 10 ga wire that according to Haynes would have been blk/red, would have included the fusible link. The brown wire goes to the volt meter and could have taken out the 10A fuse #4 “gages”.

I would suggest that you replace the wire with a 6 ga wire and a “little fuse” brand 150 amp fuse.

It is rare that the alternators will burn up. I would look close at the burnt alternator to try to find the cause.

Marine stores normally have the little fuses in stock, along with the holders.

 

[brdhrrs]

ok. so i swapped that alternator. Installed a new cable from my battery to my starter & alternator (that sucked getting to that stupid starter) jimmy'd up two burnt vacum lines and spilced on a new end for that plug(side of alt). Noticed some more burnt wires and spliced em better, elec taped then heat taped em all. then came the moment of truth. I had to boost the battery cuz it was dead. She fired up great and ram like a champ. I let it idle for a half hour cuz its stupid cold here then took her for a drive. Came back checked everything again and shut her off. And naturally when i tried to start it again everything was dead. The dummy lights didn't even come on. So i pulled the battery, which i had done yet, and I'm telling ya it looked like a fricken basketball! ahaha so bloated from the fire (massive overcharge i assume). Took it back to Canadian tire and went strait to the only parts GIRL. She didn't even notice its gigantic size or crazy shape and put it in the "charging unit" which of course it failed. Then she did up a warranty. The whole time i sat the hoping no one would notice the mutant battery sitting on the desk, and thank goodness no one did. It was only a month old but somehow i don't think the warranty people would have been too happy about replacing that fat bundle of joy! Trucks running good now. Total cost 110 bucks, which is great considering my broke student state of affairs! Thank you all for the help! :lol: