Help this idiot firgure out the fuel lines

[ecgreen]

OK, so there is what looks like a 5/16 and a 3/8 line on the sending unit. Which one is the return and which is the supply? I am guessing the larger one is the supply?

 

[adsm08]

Larger one is supply.

What are you doing that you need to know this?

 

[ecgreen]

Larger one is supply.

What are you doing that you need to know this?

First of all, thanks for the 2 second response!

I am rebuilding a 1989. I basically dismantled the whole truck this winter to paint and fix the frame. I am finally in the process of putting her back together. The fuel lines were shot and I forgot to check which line went where when I tore them out.

 

[ecgreen]

Here is a pic before I tore her apart.

 

[adsm08]

Wow, that's a nice clean body. I wish mine was that nice.

But yes, in general the fuel supply will be bigger than the return because it has to carry more volume. If you are ever really in doubt about two different sized lines, check which one the fuel filter fits into, because it is always in the supply side.