Yet another truck off the road.. Any help?

[Bradydz]

Driving home today, going a steady speed, my truck randomly made a loud bang/pop (I don't think it was a backfire, it sounded like the sound came from in front of me, whereas when it backfires, I can hear it behind me). After that, my truck started lurching and trying to die. When I rev the engine, it doesn't seem to have any problems, but once I actually start putting a load on it, it tries to die, and lurches, and did actually die a few times. Any ideas on what to look for? I have Pertronixs, so no points. And I checked my fuel filter, it is getting fuel the whole time. New spark plugs, only a month or so old.
Possibly timing?
Engine is a 355 (327 with 350 crank, bored .30 over)

[markeb01]

I had this happen years ago on a Chevelle with a 350. Driving along near the end of a 3,000 mile trip and bang/pop and the engine quit. I opened the hood and found my distributor wrenched around a couple of inches toward the firewall and the distributor cap was shattered. The distributor was tight, so it had to be loosened to pull it back around to approximately where it belonged. The cap was taped back together with band aids. The engine fired right up and drove several hundred miles home, spitting and popping from the broken cap.

When I got home I changed the cap and set the timing and everything was fine. I never did understand what happened, but having experienced something similar I would look for anything unusual related to the distributor – cracks, arcing, something broken, maybe a hold down screw came loose, distributor clamp fully tightened, timing, etc.

If that doesn't turn anything up I'd probably do a compression check and/or test things out with a vacuum gauge to make sure everything is okay internally.

[Bradydz]

Well, I believe two different problems persisted at once. We took it for a test run after the night of needing it to be towed, and the same lurching happened after a few minutes of driving. The engine started vapor locking, and eventually died. But, it would not continue running after that. Even when cold. It would start, but shut off, as if I were turning the engine back off.
We inspected the wiring a little closer by taking the tape off, and found the previous owner had made his own "splice" wire for the ignition, which had eventually fried the insulation, and the wire finally split.
After swapping the carburetor with another my dad had at the house (which seemed to solve the vapor locking problem, and the backfiring/sputtering), as well as swapping the coil (not sure if it was a problem, but needed replacing anyways), and the ignition wire, the truck is back! And I kinda like the way the different carb sounds better than the old one.

Long story short, it's back on the road!

[1963c-10]

Glad you got it fixed