engine stalling

[suttonsd]

I have a 1967 ford f100 with an inline six and a 2 barrel carb. When driving it on a hot day for about 15 minutes it shuts off and will not restart for about 10 minutes. It never overheats or runs out of gas. It usually happens when it has less than a 1/2 a tank of gas. Any ideas would be great Thanks.

[montana_hiboy]

vapor lock? bad coil? are a few of things i'd check.

[dantheman71]

I think a timing adjustment might solve that too??

[fordman]

vapor lock? bad coil? are a few of things i'd check.

i agree those are the first two things to check out.

[suttonsd]

how exactly do i prevent vapor lock and what causes it

[JMcTurnan]

I would check coil and timing, mine did that alot and it came out to be timing. Which now I got a new engine woot.

[FORDification]

I'd be willing to bet you've got a non-vented gas cap.

The next time this happens, immediately try to remove the gas cap. If you hear a whoosh of air when you remove it, that's your problem. What's happening is that as fuel is used, it creates a vacuum inside the tank, which the vented cap is supposed to prevent. Once enough vacuum has built up, fuel can't be sucked out. Letting the truck set for a short while will slowly allow the vacuum to dissipate, which will allow it to start and run again for a short while.

Simply replace the non-vented cap with a vented one, and I'll bet your problem will disappear.

[rjewkes]

is there a difference between the woosh and air/pressure comming out? i have a vented and get fuel spray is that ok? never stall just not sure if that is healthy.