My brother has a 82 F150. It has a 351. A few weeks ago we were going camping up in the mountains. While driving over a mountain pass the fuel pump seemed to have died. No gas to the carb at all. Thankfully we were close to an AutoZone and he was able to replace it. No problems at all until yesterday evening. We made it past that pass and were on the next one and the same thing happened. There was fuel to the pump but nothing after. There is a filter right before the carb and it was near dry. He took the lines off completely and put them back on. Same thing, no fuel getting to the carb.
After awhile after letting it sit it fired right up. Any ideas what this may be?
Thanks for any help.

 

If you removed the line from the carb, and turned the key with no gas coming out its not vapor lock.

Are there return fuel lines?

If so there is a "vapor separator" right before the carb. It might be clogged or bad, or just a simple clog somewhere else.

If not it could be a bad relay, they are about $10 to replace.