Read post #7 as to what started the fire.

 

I have seen and fought the exact same fire. It was on a Toyota Landcruiser. Same exact scenerio, someone hears the starter grinding away, no good. Caught fire to a much less degree, I got there and twisted off the battery cable. Smoking stopped, fire went out.

Turns out the starter stays engaged, or reengages due to the sticky solenoid.

Some vehicles are more predisposed to this condition, Landcruisers in particular between the years of 93-97 that have the 1zfe motor.

Wires in the colomn causing the short that triggers the starter is a distant 2nd for cause and origin.

 

Now that you mention that, it just occurred to me of a possibility along those lines. I'm not sure about the contacts on the 3rd gen starter, but when my '01 had the click syndrome, I replaced them and wonder if the opposite can hold true for not stopping just as not starting.

I'm probably wrong on this, but if say he turned the ignition off, and the solenoid was stuck engaged, but, the contacts were worn like mine and were on a touchy section of copper that was not making 100% contact, and then, when every thing cooled down under the hood and the metals contracted how ever many thousands of an inch different metals do from heating and cooling and say moved closer together from being expanded apart, that at that time just enough contact was made to energize the starter. I only say this because he said he didn't hear anything out of the ordinary when he went to pull his car out. And would seem a slim possibility that after he was gone things cooled down. It's a stupid theory, but I'd be speechless if someone else came along who just now saw this and had some documentation about known issues like this.... nah, who am I kidding.



The one on the right was on the battery cable side, and the other to the starter motor. Odd how one was worn more than other.

 

The uneven wear is due to the electrons flowing in only one direction with direct current. you wouldn't see this with A/C.

 

FFMike, I think you might be over analyzing this a little. But...

The tilt wheel thing is a real possibility. Think about the circuits involved. There is power to the starter relay on the starter. So only one way to get that across to the coil in the starter, close the relay. Only two ways to close that relay, close it electrically or have it fail in the closed position. Being plastic and spring loaded, it probably wouldn't fail closed. It would probably push itself apart if it got hot or break and force itself apart.
SOOOO
That leaves positive charge getting down to the relay without shorting to ground. The only way that could happen is through two exposed wires inside a harness. Otherwise it would short to ground and blow the starter fuse. Now we need to look for wear points in the harness that would chaff the wires that much. That's where I don't have enough information from you.
Ask him if he flips the wheel up and down entering and exiting the vehicle. Yes would lead to a short in the column. No would lead to taking apart the starter and check the contacts for arcing. This would let the relay weld shut.
Good luck.

 

Kelley, I hear you and agree. Only problem with investigating cause is nothing left of harness, or steering column for that matter. In fact, the power distribution center was shot ten feet in front of the truck after it fell through the fender well, onto the ground, and the front tire popping sent it forward. The pictures are a bit crude as they came from my engineers helmet cam I think, he forwarded them to me. But whatever part they have that's made of magnesium in the column finished everything off into the interior. My report as acting Lt was cause unknown/undetermined for this reason along with what he gave in his statement. If I run into him again I will check up on his use of the tilt mechanism. I'll have to check with my marshal and see if he did a follow up. What really had us was why it took so long to start cranking after it was parked. Not immediately or shortly, as he would have noticed and intervened, but over a half hour later.

 

I'm leaning more towards the fire causing more shorting which in turn caused the cranking vs. the cranking causing the fire. Some fires are very difficult to find the origin/cause, especially without hands on. If you really want to dive deep into it, and you still have the hulk, read up on electricity and fire. You could spend days and days on that truck. Although this link is more towards AC household wiring, some of the info transfers to DC. http://www.interfire.org/res_file/92114-10.asp

BTDT, have the t-shirt. Have fun, and I'm going back to morning brew. . .