Loss of power, Came and went

[alvald83]

Im looking for some help with what happened today during a long drive. Today, i was returning from a camping trip in my '69 f250, 360, AT. My truck always runs perfectly. But today after traveling at about 65 mph for about 2 hours, i stopped for gas. After gassing up, i got back on the freeway and just as i was getting up to speed it started sputtered as if it was starved for fuel. i thought maybe i hadn't switched back to my main tank but that wasn't the case. The bad thing was, as i entered the freeway it was on a fairly steep grade and since i am carrying a slide in camper, it put me in a bad position. I drove on the shoulder as i limped to safe place to pull over. i popped the hood and the engine idled normal. everytime time i'd try to step on the gas it would sputter. i turned it off and sat for about 10 minutes as i thought about calling a tow truck. after that 10 minutes, i started my truck and it no longer sputtered when i gave it gas. I jumped by on the freeway and drove home without any issues.
I had a similar experience a few years. In that case, i was driving at regular freeway speed until a sudden stop in traffic caused my truck to stall and would not start. After being towed home, it started right up and ran normal. In that case, i figured it was some type of vaper lock. i hadn't had another issue with my truck until today. Any ideas? Vapor lock again? If so, how can i prevent this?
Thanks for your help. Al

[basketcase0302]

Vapor lock will be a common issue with our old trucks Al, (try a half dozen wooden clothes pins on the steel fuel line before it enters the carb-old skool trick to dissipate the heat that usually works like a charm).

I'd also switch to your auxiliary tank to rule out issues with the main in cab tank.
I'd bet money on the issue being in the main tank itself, (but could also be a carb float or needle seat issue not letting enough fuel into the bowl).
So...many of us have had been plagued by the in cab tank issues, (especially if it has never been flushed out and resealed as rust is inevitable over the years). Many of us have also had issues with what is referred to as a "sock" on the bottom of the in cab fuel line pickup, (but i documented my OEM tank never had one from the factory). Mine was full of trash/rust/gunk that would suck onto the bottom of that same pickup so i wound up yanking/having a radiator shop acid flush and reseal/then reinstall into the truck.

What carburetor is on the truck and have you put a fuel pressure gauge on it to see it the pump is sending enough pressure, (a test fuel pressure gauge is cheap enough)? And does it have the OEM fuel pump filter assembly on the 360? That rubber "O ring" gasket on that assembly is a known source for a leak also causing issues!

[alvald83]

Thanks for the advice. I have the stock 2 barrel (i believe its a 2100). I did replaced the fuel pump a couple years ago. i guess i can get a fuel pressure gauge to rule things out.

[davelj]

It's possible you picked up a bit of water when you gassed up.