Electric fuel pump "vertical" mounting position

[Paul Bjarnason]

I am installing a Carter electric fuel pump in my '29 Model A, along with a Holley fuel pressure regulator, because I am using a Weber carburetor. The instructions to the Holley fuel pressure regulator say the fuel pump should be installed "in a vertical position with the pump motor on top." This does not make sense to me. The Carter fuel pump instructions say nothing about mounting in in a vertical position. I was planning to mount the pump on the frame rail below the carburetor in a horizontal position parallel with the frame rail. I don't see why a vertical position is necessary and there will be a positive fuel pressure in the line due to the high position of the Model A fuel tank. Does anyone know why the fuel pump needs to be in a vertical position, as stated by the fuel pressure regulator instructions? Thank you.

 

[Jim Brierley]

I think it makes little to no difference which way the pump is mounted. I would follow the Holley directions for the Holley item and the Carter directions for the Carter item.

 

[Phil Brown]

Holley likes their fuel pumps mounted motor up so if the shaft seal starts to leak the motor section will not fill up with fuel (bottom section has small drain hole) Electric motors with brushes and gas not a good combo