Went for a drive in my parents '66 Bird and it seemed to "run out of gas" when I mashed thepedal once I was going about 45 mph. Pulled over and the engine reved fine. Pulled out and the same thing. When I got back home, there was gas leaking from the filler cap. Now this car sits alot, and I don't know how much gas is in the tank since the gauge doen't work. But I don't think it was so full as to slosh back out the filler neck.

I'm thinking fuel pump or carb or both. My parents bought this car new and as far as I know it has the same carb as the factory put on it. The tag reads C6SFA, and C6AA in smaller digits below the first set of numbers. 390 engine also. I didn't look, but is there a fuel filter attached to the pump? This could be the problem, but I have seen blocked filters completly cut off fuel supply. In my case it only seems restricted.

Anyone have this type of problem? Is there a fuel filter that is a part of original equipment they may be blocked? Is the pump bad and pressurizing the tank? There is a vented cap on the tank.

Thanks.

 

Flowing dually. Sounds like fuel pump.

 

Then again hyper-vacuum from a partially blocked filter could cause it too.

 

Put on a new fuel filter yesterday, no change. I actually sat in the driveway with the engine reved up, maybe 2 grand, for 20-30 sec. and the engine did not fall off. But on the road it stumbles/loses power at around 45 mph.

 

In carb try new accelerator pump. Actually used to be a $0.50 part but now I think they only come in a kit (though I could probably still order them seperate). This is one often forgotten little bugger. 4 little screws on the front of the carb and it's right behind there - BE careful NOT to strip them when reassembling it. If the car sat I can almost guarantee you'll even see the leakage/seepage if you can start the car with the air cleaner off. Next I'd see the fuel is filling in the fuel bowl - when it shuts off if there's an empty fuel bowl therecould bea problem with the fuel pump or carb float (run any ford carb with the top off if you have a smooth engine). A float can be checked by immediately removing it, drying it off and first inspect the solder joint and shake (listen for liquid inside - if so it's shot) then sink it under water in a sink and wait a few hours - go back and recheck for liquid inside. I hope this helps. It about covers the old fuel systems.