Fuel Pump Position, Will It Work?

Okay, kind of a new guy question. I am rebuilding my fuel system in the ‘51 M38 and am going with a Holley Mighty Mite electric fuel pump. My M38 is already 12v and previously used a similar little pump that delivers 7 psi. Worked great.

So here’s my question. The instructions say to mount the pump below the lowest portion of the tank, and it’s designed to push fuel up to the carb... not suck fuel from the tank. I have it mounted below the tank (inside the frame rails below)... but the fuel pickup brings fuel UP VERTICALLY to the top of the tank, then into the line, and then down to the pump.

Is this going to be a problem since the pump supposedly doesn’t suck? Or once siphoning action starts will fuel be able to travel up the pickup feed to the top of the tank, then down the line? Maybe I’m over thinking this?

Thanks.

 

I'ld expect to prime the pump, once it's primed it won't know the difference unless it looses its prime.

 

I would expect the pump to self prime especially so if the tank is near full. Your instructions say the pump is designed to push fuel. That doesn't mean it won't draw enough fuel to fully prime itself.

 

okay, that makes sense. Thanks for the help guys.

 

Yup. Just make sure the tank is full when you put power to the pump. You could even fill it up to the cap for this exercise and then you would have gravity flow for the prime. The only real downside is it you let the tank go dry. You may have to repeat the process out in the sticks. My EFI pump in my 3B is mounted the same way and I use the same prime process. I'm careful not to run it out of gas but the 24.5 gal tank really minimizes that problem.