I'm out of ideas and need help. I've been having problems with my starter system for months. I have a 1985 F350 w/7.5. A few months ago, when I tried to turn my key to start the truck, I noticed my starter solenoid smoking, and the starter would not activate. After a few attempts, the solenoid got so hot, the positive wire melted off. Ok, So I replaced the solenoid, and everything worked for a few weeks. Then the same problem happened again! Replaced the solenoid again, and everything was ok for a few more weeks.

But now I went to start the truck; the starter isn't doing anything, and I'm getting smoke coming from inside my dashboard. I thought it was the starter switch on the steering column, so i replaced that. Nothing. I tried replacing my starter just to see, and still nothing. Every time I hold the key on the start position, I get a little smoke coming out of the dash. I can't see wheere the smoke is coming from. WHAT IS THE PROBLEM!?!? I'm guessing now so any advice would be helpful. There might be something I didn't think about. Thanks

 

If I Hotwire my starter and connect the positive wire to the battery, it will spark violently, but the starter will start

 

Smoke from the dash is not good and before I went any farther I would check where it is coming from even if you have to pull the dash apart.

Once you find and fix the dash smoke I would replace ALL battery cables and don't tell me "they look good" as they can still be bad.
There is a post on how to check them do a search

sparking when jumping like you did is normal as the starter pulls a LOT OF AMPS!
if you go from batt posative to the small S lug what happens?
Dave - - - -

 

Wiring diagrams for an '86 here:

Start & Ignition - ???Gary's Garagemahal

What brand of starter solenoid did you buy? Was it name brand like MotorCraft or AC Delco? Or was it an offshore brand like Fling Dung?

The present fault of smoke under the dash means you've got a serious overcurrent in the starter control circuit. Don't worry about the big battery cables or the starter at the moment. It's the small wire from the ignition switch to the solenoid that's carrying too much current.

If you melted some insulation under the dash, I'm surprised fuse link M didn't open. See page 26 at the link above. There's no fuse in that circuit, just the fuse link.

The solenoid is the most likely culprit for overloading that circuit. It's basically a big electromagnet controlled by the ignition switch. That electromagnet in turn moves contacts that route power to the starter.

Try this for troubleshooting: Disconnect the big cable on the solenoid that runs to the starter. The starter obviously won't turn. Now turn the key to start. Listen for the clunk as the electromagnet in the solenoid gets powered. See if you still get the smoke.

You will still have to get under the dash to find the overloaded wire and replace it. But for now it's important to find and fix the cause.

 

I purchased 2 different solenoids from Pepboys. The first was the more expensive brand. It lasted for a few weeks. Then I purchased the cheapest 1 they had. That is what is on my truck now. I'm not sure of the brand name

 

I appreciate the tips. I will try what y'all recommended, and give you an update

 

I would first check to make sure the smoked wire(s) under dash are safe enough to start using again before doing any thing else.
If it is not safe you may let the last of the smoke out before the fire starts!


I find if the cables have too much resistance it will not pull the solenoid in all the way and it could the smoke solenoid.
I don't know how that could over tax the key start circuit, it just would not pull in the solenoid no?
Dave ----