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I worked on her car, now its on fire

My friends 99 Ford Toris broke down at my house one night over the weekend. She said that she had seen smoke coming from the hood so she turned off it off. Being an upper class-man of mechanical engineering and part of SAE racing team I felt inclined to tell her that I would take look at it even thought though the only real car I have worked on was my 92 Volvo 940. I popped the hood and found the serpentine belt lying tensionless but in place. After few trip to the auto store I finally got the right belt. I open my toolbox to find it in disarray and the one wrench I need missing, I should have expected this with six roommates. Being young, confident and striving to impress this girl, I pull the belt into place. I turned the key and the engine cracked slowly. So I jumped it for a while and it still was turning slow. I go back to the auto store to test the battery and leave with a new battery. I put the battery in the car the engine turns a few times and I hear ?FIRE!!? There is a small fire in the bottom of the engine that I am able to blowout but only for a few seconds. I now try to disconnect the batter and find that the wires to the battery have turned into a heating coil. I manage to get it disconnected with only a few burns. The only good that came out of working on her car is that she is now buying me dinner. Now the car is still sitting out there and her farther is coming on Friday to look at it. I think that a ball bearing in the water pump failed and the new belt with the new battery fried the starter. Is there any truth to this? Did I do some thing wrong? Should I take responsibility for the fire? And can I fix it?


OUCH. Sounds like multiple problems, not your fault. Might be some kind of short in the starter system, that killed the old battery, started the fire. For the (unbroken?) serpentine belt to be lying in place would mean the tensioner pulley was bad…was it? Find a buddy more up on cars, see what they think.

It sounds to me like you may have hooked up the battery cables in reverse order. That might have caused the latest fire, and it is easy to do if the battery cables are not color coded correctly.

When your friend first saw smoke coming out of the engine compartment, did it smell like an electrical fire, burning oil, or burning rubber? I had an old ford that had an emission pump seize. It made the belt smoke and squeal. I am willing to bet one of the pullies seized, maybe even the alternator.

You were valiant and tried to be helpful. Sometimes, something like this happens to the most experienced mechanic. Them gremlins get into everything.
I think that your plan B has merit.

I am guessing something (a pulley) was stuck and that is why the 1st belt broke. The second one was going to fail too. The heat was probably from the friction of the belt to the stuck pulley and then you have fire. Not necessarily your fault, esp since this is only one explanation.

The old belt was broken and you could see where the flywheel burned through it. Im not shore that the tensioner is calibrated right but i know it works cause that is what gave me the slack to pull the new belt in place.

I thought the same thing about the cables and it was the first thing that I checked for. As far as the fire goes it was an electrical fire.

There is a small fire in the bottom of the engine that I am able to blowout but only for a few seconds. I now try to disconnect the batter and find that the wires to the battery have turned into a heating coil.

I had a bad starter out of the box that barely turned the engine over once before stalling and nearly burned the car to the ground. It started smoking almost immediately and the battery cables were roasting hot by the time I got to them. Even though the key was OFF, the solenoid was stuck on and the insulation was on fire in less than 10 seconds. It was a struggle to disconnect one of the terminals without getting burned too bad. So your story sounds very familiar to me.

Try this: the alternator is creating a dead short. Eventually it got hot enough that the belt started coming apart on it, or it just seized altogether. That’s causing your short circuit, that caused the belt to come off.

With the battery disconnected (and well-away from the car), remove the serpentine belt and see if the alternator pulley will spin. I’m guessing that it will not. Regardless, take it to have it tested at your favorite auto parts store. Most all of them do it for free. When the alternator shows up as faulty, replace it, as well as the battery cables that are probably fried now. While you’re doing the battery cables, crawl under and investigate the starter and the connections to it. It could well be bad, too.

I’d bet that you’re golden after that.

There is a shop nearby here and near a couple of local universities that hires a succesison of engineering students on a part-time basis. I think that it works well for everyone involved. It would seem like a good thing for a ME student.

The thing you did wrong was to not look for the root cause of the belt lying loose.

Things break for a reason. While it often is because they’re just plain worn out, it’s often not. It’s always prudent to go looking for a cause as well as any other signs or symptoms of anything that might be related. Diagnose then diagnose some more until you’re sure you’ve found the root cause.

Let this be your guide when you start in your chosen profession too. You’ll be amazed at how many things are not what they appear. Failure analysis is an art that you’ll learn to appreciate.

Sincere best.

Surely an “upper class-man of mechanical engineering and part of SAE racing team” would know the difference between a Taurus and a “Toris”. But I digest.

Anywho, whilst I’m no SAE mechanic, my spider-sense tells me that the tensioner failed, and the slipping belt created enough heat to cause a nearby electrical wire to lose its plastic/rubber insulation, which in turn may have created enough of a spark to ignite the greasy/oily crude that had been collecting near the bottom of the engine bay.

Surely someone with “spider-sense” (is that like “Spidey-sense”?) would know the difference between digressing and digesting.

Sorry, couldn’t resist. No offense intended.

Never fear, I shall enlighten you.

Consider me enlightenheaded.

Have a cool weekend.

Well, as has been said here, you should check all pulleys with the belt off to see if any are frozen. But I can’t quite figure the fire.