I am in the process of swapping an L98 into an 86 that had a carb'd 305. I picked up a fuel pump/unit, and I'm trying to figure out what lines need to go where. It has 4 lines coming out.

One line is obvious, it has the connector for the TPI fuel feed (screw-on coupler).
One line goes to a vapor/liquid separator.
One line goes down to the base of the fuel pump, like a return.
One line goes through the mounting plate and ends about a half inch inside the tank.

The main feed is obvious, my question is, which one is return (the one that goes to the bottom of the assembly?), which is the line to the vapor cannister under the hood... and what is the 4th line for????

I have the old assembly for the carb setup, but it has two lines that end a half inch inside the mounting plate.

 

Vapor/liquid separator?

The return line is 5/16" and goes to the bottom of the pick-up. The carb return line just goes through the mount plate.

The 1/4" line is the vapor recovery line. It should go to the charcoal canister in the engine compartment.

The larger line which just goes through the mount plate is an air inlet line connected to a breather valve up above the axle.

 

Thanks for the info. Below is a pic of the liquid/vapor separator, it's the silver/black part on the right. At least, that's what the manual calls it.

 

Okay, hadn't paid attention to that part, nor heard it called that. Good to know.

That line should go to the charcoal canister.

The main difference, other than the fuel pump itself, is that the return line goes to the bottom of the tank, unlike the carb pick-up.

 

Five hours to get it all apart... 2 hours to get it all together. I really hope I have the pump and sending unit connected in the tank correctly. Would really hate to take it all back apart again. So now the rear is back on the ground, with no parts left over, not even a screw... which means I goofed somewhere

Next up, lifting the nose and yanking the engine and trans, but that can wait for tomorrow to start.

Thanks for the info, five7kid.