Black smoke from defrost vent

[Dirty1]

I tried a search and nothing came up.

Here is the story. I started the truck today and let it warm up a bit. I drove it for about 10 minutes to my buddy's shop to do some welding on the plow frame. Nothing was different than any other time I drove it.

After we were done I left the shop and went to he store. Again nothing out of the ordinary. When I left the store, the truck started fine but as I began to drive off there was thick black smoke, that smelled like an electrical fire, that was coming from the defroster vents. The defrost was on at this time.

I pulled over, shut the truck off, popped the hood and let the cab air out. I started looking for the source. I could not find anything. I was able to drive the truck home with the defrost off and there was no more smoke.

What do you all think? Is it my blower motor? I disconnected the batteries for the night.

 

[mudman]

Yep, Blower motor.

 

[doghead]

I'd suspect the blower resistor may have failed or had a mouse nest cought fire from it's heat.

Easily inspected and tested.

 

[Dirty1]

Thanks for the replies! I will take a peak tomorrow. I was just worried that my truck would burn in the driveway while I was at work tonight.

 

[wayne pick]

Did you disconnect the bateries before welding? Bad grounds and old wiring can do some not so funny things when welding is is done with the batteries connected. I blew out every single lightbulb on a garbage truck this way many years ago. Just a thought.

 

[Dirty1]

I had the same thought. I asked him about it prior to welding but he said it would be fine. I guess I learned a lesson today.

 

[dstang97]

Always disconnect your batteries when you weld. I once fried all of my gauges in my k2500 because I was being lazy.

 

[dstang97]

Also mice love heater boxes. I know of a few that have caught on fire. I really need to take mine apart and inspect.

 

[MarcusOReallyus]

I had the same thought. I asked him about it prior to welding but he said it would be fine. I guess I learned a lesson today.

Find another welder.

 

[Skinny]

Turn the boost down on the blower motor or rotate the fuel screw counterclockwise a 1/4 turn...

 

[wayne pick]

Good one Skinny!