Hi I'm new to the site and I have a 77 F150 4x4 351m and a c6. The problem I'm running into is that when its hot outside over 80 and I sit at a red light or anywhere for more than about 30 sec the truck will vapor lock. I know this because I have a see through fuel filter by the carb. you can see it shooting air instead of gas. If i let it sit and idel for about a minute it will work its self out as long as im easy on the pedal. If i floor it to take back off it will do it again. Any suggestions will be greatly appreciated thanks.

 

What is your fuel pressure at? What filter are you using? See through (never heard of that one)

 

I have a brand new fuel pump from advance its showing 7 -8 pounds. Its a clear canister type filter you can get anywhere.

 

Rerouting any hard fuel lines away from the engine will sometimes keep them cooler, so I have been told. If they are leaning up against the engine block the gas will vaporize readily. The key, as I understand it, is to keep the gas in the lines as cool as possible under the circumstances. Replacement electric fuel pump at the gas tank is another option in lieu of the engine-driven pump.

 

who makes the fuel pump? I've always used Holley and never had a problem.

 

I belive airtex or something like that. I drove it about 100 miles today with the a/c on and when i hit a hill or something that required more gas it would try to vapor lock. So when I got it home i let it idle and i could see the fuel vaporizing in the filter between the carb and fuel pump. I was told that the fuel filter inbetween the carb and pump may be a problem and im going to try to cover the fuel line next to the manifold.

 

Make sure none of your fuel lines are close to the exhaust; make sure none of the rubber fuel hoses are pinching shut; finally make sure your fuel tank can vent properly.

 

i just bought a truck here in arizona, it is acting the same way as yours. my post on this site is called SOS stranded in arizona. I can drive the truck almost exactly 3 miles then I think it is either vapor locking or sucking air into the fuel. did you ever get yours fixed? any ideas on what I might do? I am hoping installing an electric fuel pump will help me get the truck 1200 miles back home.

 

If you have the clearance, put some plumbing insulation over the fuel line to the pump along side the motor. I had an issue that way years ago and that took care of it..