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Hot Electrical Stink

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Old Oct 4, 2019 | 12:25 PM
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Hot Electrical Stink

Under hood, passenger side.

Using a wrapping paper tube & with my snoz poked in one end, it seems to emanate from the area of HVAC box.

I can turn my electric fan off (no it's not that) so there is no drafts when the engine is running & use the tube to "sniff".

Not coming from the starter or it's wiring or anything on the drivers side.

When the fan resistors (or fans themselves) give up the ghost, do the start to give hot electrical stink?

Tried this theory out by driving around with heat/ac completely off & seems gone. (some odor, I've just worked on the exhaust)

Ideas?
 
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Old Oct 4, 2019 | 05:34 PM
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Originally Posted by Scndsin
Under hood, passenger side.
Using a wrapping paper tube & with my snoz poked in one end
I think we need pics :P
I can turn my electric fan off (no it's not that) so there is no drafts when the engine is running & use the tube to "sniff".
Not coming from the starter or it's wiring or anything on the drivers side.
When the fan resistors (or fans themselves) give up the ghost, do the start to give hot electrical stink?
The insulation on the fan's motor certainly will have the smell but they're certainly not long for this world once you start to smell em.
I'd guess the resistor could be going bad too. They're usually cheap enough.
On that side there are a couple other electrical things like the AC pressure switch but I wouldn't think it would make any smells.
Pretty sure the horn relay is over there too inside the cab tho.
 
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Old Oct 4, 2019 | 07:32 PM
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if resistors are on the medium/big(wattage) size, they can smell like a motor when it starts burning the varnish cambric tape off them, then the magic blue smoke, soon leaves.
 
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Old Oct 5, 2019 | 12:53 AM
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I've never torn into the HVAC box. Getting ready for a road trip.

Is the resistor accessed inside the cab or under hood?
 
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Old Oct 5, 2019 | 01:49 AM
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Originally Posted by Scndsin
I've never torn into the HVAC box. Getting ready for a road trip.

Is the resistor accessed inside the cab or under hood?
Under hood, just below and a little to the right of the blower motor.. Be sure to check the plug, any discoloration is probably too much, if it's getting hot it will most likely be the stinker...
 
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Old Oct 5, 2019 | 07:19 AM
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Sounds like what someone posted when their truck burned up.
Leaves and debris touching the resisters started the fire.
There were also photos of the truck burning on this site back when it was posted.

So do not turn on the fan until you clean out the junk from the resisters.
 
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Old Oct 5, 2019 | 08:18 AM
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Originally Posted by White 97 xlt
Under hood, just below and a little to the right of the blower motor.. Be sure to check the plug, any discoloration is probably too much, if it's getting hot it will most likely be the stinker...
Thanks, I thought it was in the cab behind glove box area. Will check this AM.

Originally Posted by subford
Sounds like what someone posted when their truck burned up.
Leaves and debris touching the resisters started the fire.
Yes, what I certainly was trying to avoid.

Have scrupulously tried to keep everything possible out of the cowl, vents & other areas
 
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Old Oct 5, 2019 | 10:49 AM
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Subford called it on the trash. Had no idea it could get down that far.



Unfortunately I can't find any residual stink on the resistor pack or the fan.

Ran the fan & sniffed on the motor vent, nothing.

No distorted wires or connections

Coils on the resistor pack clean & silver. Thermal fuse MAY have some discoloration or it could be dirt.

Bill do you have a value, rating or some # on that fuse? Not that I could find one today.
 
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Old Oct 5, 2019 | 11:07 AM
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From: Easton,Ks
What fuse???
 
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Old Oct 5, 2019 | 12:49 PM
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Thermal fuse on resistor assembly.
 
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Old Oct 5, 2019 | 01:03 PM
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From: Easton,Ks
Order the part from NTE Electronics. It is 121 degree C value and it comes with little crimps and instructions.
More info:
https://www.instructables.com/id/Blo...e-Replacement/

Name:  CmEtk1S.png
Views: 26
Size:  278.4 KB
/
 
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Old Oct 7, 2019 | 03:09 PM
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Solved. A spark plug wire seperator had come apart.

It fell down on the header & since they are wrapped, it did not fully melt & burn.

While checking timing, saw a little wisp from tween 3 & 4, hit it with flash light & there it was down leaning from boot to header tube.

Thank you all who responded. Just thankful it wasn't a fire hazard & I got the trash off the resistor preventing another.
 
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Old Oct 7, 2019 | 03:22 PM
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Good thing you found the root cause before the truck caught fire..



More in this thread: So My '96 Burned to the Ground Last Night
 
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Old Oct 7, 2019 | 05:14 PM
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Never-ever saw that one...

Don't know how I missed it.

Thank you again 97xlt & subford.
 
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