[66nova guy]

Hi!

If my -66 Nova Wagon has been parked for two days or more the gas seems to run back into the tank. The clear fuel filter before the carb is empty and I have to make several attempts to start it before the fuel gets pumped up to the carb again.

So, is there some kind of valve in the fuel pump that has stopped functioning?

[Pony]

Next time you park it leave the gas cap loose. If the vent is plugged or it's not a vented cap you could be creating a vacuum in the tank (pumping the fuel out with no way for outside air to enter and equalize the tank pressure) and when you shut it off it's sucking the line/pump/carb empty trying to equalize it's pressure with the outside world.

[western star]

I had that same problem and it turned out I had a pin hole in the diaphram in the mechanical fuel pump. Replaced pump and ta duh....fixed. Worth a look.

[Kevin45]

My vote is for a bad fuel pump also. Just like holding your finger over a straw. As long as there is not a pinhole the fuel will stay in the line. Small pinhole and it will run back.

Kevin

[camaroman7d]

I would agree it's the pump, this is a typical symptom. The pump should prevent the fuel from bleeding back.

A vent problem would typically show up while driving, by starving for fuel or stalling. Sometimes it will cause hard starting (hot) as well.

[Dubz]

you could always put in a one way check valve in the fuel line, but as mentioned the pump may have a problem

[4 Jaw Chuck]

Replace the pump, check valve is leaking.

[66nova guy]

Thanks guys! I have a pump with 3 fuel lines from a ´79 van. Can it be made to fit my 60s 327 by plugging one of the lines?

(I have the same problem even if I remove the gas cap when parking.)