Change the fuel pump. You've got a bad outlet check valve that's letting the gas flow back through the pump and it's having to pump the line full. BTW, the only thing pumping the pedal is doing is giving you some leg exercise. A dry carburetor doesn't manufacture any fuel by pumping the gas pedal.
Jerry
It's a mechanical fuel pump, I don't know how old or what manufacturer, but there is no return line, just the feed line from the fuel pump to the carb.
