Packard Forum Index » Post-War (1946-54)

Love your user name!!!


Seems to me that, once upon a time, we drilled out a surplus fuel tank cap and installed an air tank fill valve so we could pressurize the tank a bit to coax fuel to the pump. And as I recall, it worked.


Another trick that some folks do it to get a low pressure electric pump and install that out back near the tank with a toggle switch installed under the dash. They'll turn that on and run it for a few seconds to prime the mechanical pump so as not to have to saw on the old starter to draw up the gasoline. I'm still not sure how a sound fuel system will drop the prime like these do, but they do.


Good luck on getting your issue sorted.

I'm convinced fuel being sucked back into the tank is caused by a valve in the fuel pump not seating/sealing correctly. Grit or varnish in the pump could cause that.

I not sure what pump he got or condition of his vehicle, that aside there has been a number of manufacturer issues with mechanicals since manufacturing was switched to MX and consolidation of the supply. I went through 4 on the Cad B4 I converted to a noisy electric. The check valves are at fault.
These may benefit from "priming" before you try to suck air until the gas flows. Not exactly designed to pump air. Low suction head device. Fill the outlet line and pump with gas to create a better seal and have some head to pump against.
I've had better success rebuilding originals. Unfortunately, I threw the Cad's out. But rebuild worked well on the P with its dual function pump.