Check out the threads on hot fuel return if you have vapor lock problems. I came up with a system to take care of vaporlock but later found that Ford was already using it on the 460. Parts may be available from Ford, just look up the "hot fuel return" system used in carbed 460's during the 80's.
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I have come up with a number of ways to prevent vapor lock. I have used the system you are speaking of by using a fuel pump that has a return line going back to the fuel pump. That way the fuel keeps moving with cool fuel constantly moving through the fuel pump, thus preventing vapor lock. Lincoln was the first to use this system starting in the late fifties. Years ago we had a 64 Ford F-600 that had a 352 that had a bad habit of vapor locking. The engine was replaced with a 462 Lincoln engine. The Lincoln engine had a return fuel line on the pump so we routed a return line to the fuel tank to take advantage of the system. The truck never again vapor locked. Another advantage was the Lincoln engine was such a torquer that the had a tremendous gain in power. We changed the rear to a higher ratio and actually had a truck that we could do highway speeds comfortably with.

Michelle

 

The fuel tank makes a large heat radiator

 

If it wasnt for the fact that the truck starts up after sitting a while, I would think maybe your distributor roll pin started to shear, your timing got set off a little bythe movement, and that is causing it to want to die at idle....My truck ran for a while with a partially sheared roll pin, same symptoms, except for the starting again....But souns like the Ignition module is most likely the problem...

---JOHN

 

i found a dilly of a breakdown once, one of the wires inside the dizzy broke off the doohicky. when the engine started and pulled vacuum, the wire would pull away from the doohicky. when the engine died and lost vacuum, the wire would make contact again and start right up. and die again. kinda got lucky finding it as fast as i did. i pulled the dizzy, put in a new doohicky and drove it out of the burger king parking lot. it was an olds, but could be a similar thing going on? or not.

 

In 1972 I bought a new F-250 with the 390 engine. The truck was about a week old and I was driving down a highway doing the speed limit, when I got ready to pass a car and accelerated the engine died, as soon as I let up on the gas it started running perfectly again, this again happened whan I pushed the gas to the floor, and once again it ran perfectly when I let up on the gas I pulled to the side of the road to check it out and low and behold I found the the coil wire (dont remember if it was + or - makes no difference) was caught in the accelerator spring, when I would go full throttle it would gently pull the wire back off the coil and it would die, as soon as I let off it would reconnect just enough to make contact and the engine would run perfectly. I wish all stalling problems were that sinple.

Michelle

 

if not the module box, or the coil, then it's the pickup coil in the distributor. I'm leaning toward the pickup coil because, I've gone through two in the last 7 years or so and they would give the same EXACT symptoms. The module box that's that's over by the fenderwell (I guess they put them there on the '77) can be tested at parts stores such as autozone or advance. Many times if it's the module over by the fenderwell, you can dump icewater on it when the truck dies. If it restarts after dumping icewater on it, then for sure that is the problem.

 

OK everyone, this one is solved - it was the ignition module as Torque1st predicted. I swapped in a new module and the truck is running great again, all the symptoms are fixed.

Thanks to all who replied.

Burritoman