My '31 has a '33 motor. I just recently had the gas tank reconditioned & installed a new fuel pump.The car runs fine once started but I've noticed that if the sits for a day without being run I have to crank it over quite awhile to get the gas back up to the carb. I've disconnected the gas line from the carb & noticed that once the gas flows out of it, it starts retreating back down the pipe. The gas on the supply side of the fuel pump is also empty when checked. I checked the fuel pump to see if it has a check ball & what it has is a thin plate with a spring that works as a check but not very well. Is there something missing like a inline check valve or in fact this is how it's suppose to work? I don't recall having this problem in the past.

As always thanks for any info you can share.

The check valves in the fuel pump are not properly sealing. They should only allow fuel to move from the tank toward the carburetor. Any return flow means they are leaking.

Could be a piece of trash, rough seat, weak spring or damaged valve plate.

Thanks for the info regarding the springs, etc. I took a look at them & found the one on the discharge side to carb was broken. I tried straightening it out & it seems to work but the gas still trickles back down. Does anyone happen to know where replacements springs can be purchased as I really don't want to use the car for fear the spring will crap out? I don't want to have to purchase another new AC pump just to get the springs if I can help it as it is only 5 months old. I check my local auto parts store & they did not have anything. Also our hardware stores had springs but nothing close in resistance or size that would work..........Thanks

The Filling Station has fuel pump repair kits. Anytime that you need parts always check their catalog first since they have a lot of stuff.

You may also find that the seat in the fuel pump is not smooth. It must be smooth and even for the wafer to seal. There is a tool to dress the seat or you can make one from a dowel with small piece of sand paper glued to the end. Be sure that it is straight and twirl it to dress the seat smooth and even.