Quits running, and smoke from under the dash

[roblf250]

Hi all,

I've done some searching here without results, so I guess I need a little help.

I'm not sure where to post this. I've got some engine trouble, but I'm highly suspicious that an electrical problem from under the dash is the culprit.

So here goes..........

My pickup (72 F250 4x4 - 360 - all stock) will run fine for 5 - 15 minutes, then all of a sudden quits running. If I try to keep it running when that happens (give it a little gas), it just bucks and backfires through the exhaust (Chug , Chug, ...... BANG!!! - Dang that's loud).

Here's what I've done so far:
* Replaced the plugs, wires, cap, rotor, points and condenser.
* Tried a different coil.
* Checked the vacuum advance on the dist (sucked on it - no leaks, seems to work)
* Replaced the in-line fuel filter
* Rebuilt the stock Motorcraft carb.

When I first start it up, it seems to run a bit better than before, but then the same problem happens. Chug Chug, ....... BANG! So, no real change.

Here's why I posted this here.....

The latest symptoms -
* Right before it starts to do that, the temp gauge goes all the way up.
* When I try to restart it, I get smoke from under the dash!!!!! Yikes!

Related problems?
Thoughts?

Thanks,

Rob

[heep70]

Dang, I am not real good with electrical. I would check out the resistor wire from the ign switch to the coil. It may have melted into others. Also check the ing switch itself.

Hang in there, Someone here will surely point you in the right direction.

[FoMoCo]

I had typed a page about the pink resitor wire but deleted it thinking it may be the wrong thing to check. Check out the FORDIFICATION wiring diagrams. Look for the temp unit and pink resistor wire.

Nick

['75-4x4guy]

Does the smoke smell like melted wires ?
If not them maybe the smoke is actually stream from the heater core ?
You said that the temp gauge was pegged then maybe the engine is really overheated ..
But then again if the wires are melted then the temp gauge lead might be grounded-giving you the pegged gauge.

[bluef250]

Actually, it sounds like the distributor is not distributing. Bushings are gone and points are closed all the time. Might act like a short, wires get hot, then smokes if old or if some foreign substance on them. Since engine backfires timing is off. Mine acted like that, distributor was bad. Had 10 foot flames coming out the tailpipe. Engine gets hot because of unburned fuel, bad timing. Hope no damage has been done. If the shaft wiggles and you cannot keep the points set, it is time it replace the distributor. You can keep it stock or install OEM or aftermarket electronic unit.

[morganater]

I had almost the same problem. MY fusible link (which is supposed to be PINKISH) but is really like brown-pinkish and is all soft and fatty from years of use.... It burnt up. You can buy these at stores it runs from your ignition switch to your coil.