Hello gents I have a 1968 F100 long bed and am looking to install in-line fuel pump the in cab tank has been deleted, when I got the truck the fuel lines were all undone not sure what ones go where any help on this would be great

 

Well, I assume you have one gas tank now so configure the system so that the fuel goes from Point A to Point B.


Or do you mean what to do with the manual fuel switch? Unclear.

 

I have two lines in the side of the frame what one is the feed and what is the return

 

There is no return line on a stock carbureted setup.


Still unclear to me... trace the lines. Are you saying that you have two hoses come from the fuel tank???

 

Clear photos of what you have would make it easier to understand your setup and what you would need to do.

 

As Hio said, there's no return line on a stock carbed setup. Where is the current fuel tank? Dual tank setups had the main tank inside the cab and a saddle tank under the left front of the bed with a filler through the side of the bed, these could be factory installed, (though I'm not sure if dual tanks was an option on F100s) dealer or aftermarket installed. There was a valve to switch between them usually installed on the floor just inside the door under the edge of the driver's seat, under the floor in that spot is where the three fuel lines (one from each tank in and the 3rd out, up to the fuel pump) would connect to the valve...is this where you're seeing an extra fuel line? If the main tank was removed perhaps the valve was removed too?


If you plan to install an electric pump, just be aware that they are made to push fuel, not pull it, so the pump needs to be mounted down low fairly near to the tank. If you have to reconfigure your fuel lines a bit to make it work, what you are looking for is basically this: short length of line from the tank to an inline filter before the pump, then the pump itself, and then the main run of fuel line to the front of the truck and up to the carb. You'll want to delete the mechanical pump which usually had it's own built-in canister filter, you can leave it in place or remove it and install a block-off plate. I prefer to remove a component that's doing nothing. Depending on what carb you're using, you may have a small filter built into the carb right at the fuel line connection as well.

 

I'm running both an electric and mechanical pump on my truck. It sits a lot and I'll prime the engine with the electric. I also have two tanks and will use the electric to get fuel to the carburetor after running one tank dry.