What kind of functional problems would you encounter if you had the fuel evaporator and fuel return lines swapped at the fuel tank?

I'm pretty sure I have it in the correct order.

The outer most line (top view of the fuel tank) is the evaporator line since it runs to the highest point of the fuel tank. The fuel feed is obvious with it's coupler being a compression fitting. The fuel return goes along the feed to the fuel pump.

J

 

To me, if the lines were swapped near the fuel tank, it should have the same result. The fuel return line is slightly lower than the fuel evap line. Maybe there is a difference with a full tank?

 

Sorry for the small pictures, but I was trying to show the fuel return line stops a few inches below the fuel pump cover.

 

I don't think there would be a problem with the return and evap line swapped at the tank. Sounds like you have them correct with your description... evap should be the highest.

Just make sure not to send your return like to the canister... lol

 

I can think of one possible problem with having them switched. In my 93 ext-cab there is a containment wall around the fuel pump that will catch fuel from the return line. This effectively makes a small holding area within the tank so when you are low on fuel, your pump will be less likely to suck air. If you had the lines switched, the fuel may not be dumping into the containment area of the tank (if you have one).

 

Here's a pic of what I was talking about: http://community.webshots.com/photo/...42310107YGZVCs

 

Does your fuel pump "howl" as the fuel level gets low?

 

Talking to me? Mine does but I have a Walbro 190 and they are known to sing a bit. It does get worse when the tank is low.

 

I have a Walbro 190lph too. It'll definitely let you know when it's on and low on fuel.

 

on a 85 with 22RE, there is a prob if they are swapped

it functioned normal while driving. But, when stopped, and the tank got warm and fuel expanded, the lower line (should have been return) pushed fuel into the charcoal canister, and out onto the ground.

The vent is at the top of the tank, and it would not allow that to happen because it is above the fuel

 

I was just going to say, You will end up with a puddle of gas under your rig if backwards as it expands and spills out the charcol canister.