Fuel Sending unit lines ?
 

I have my new sending unit, it has 3 lines I will only be using the large draw line from the tank to the fuel pump.

I did away with the canisters and there is no return fuel lines.

What should I do with the other two line outlets on top of the sending unit ? plug em ??? do any need to breath ???

I plugged my return lines off when I replaced the fuel line to the pump from the valve on the bed rail. The other I think is a vent but I routed my vent lines together where the charcoal canisters were. I would vent one with a breathable cap where fumes go out but nothing comes in.

breathable cap ????

It's a cap that goes inline. It's a vent cap like on the rear axle. It has a vent tube there as well.

Where can you buy it ?

Not sure on that. Probably a auto part store. Tell them you're looking for a cap for a line that needs to breathe but still be able to keep stuff out.

I'm just wondering if you can still buy vented gas caps. They probably don't sell one to fit a unleaded fuel tank. I'm not even sure you can buy any vented caps anymore.

But, if you can, you could cap off the vent/charcoal canister line. If not, you will need a filter/cap on this line so gas vapors can escape the tank, or else it may just rip the tank wide open. I know you've seen plastic gas cans blow up like a balloon when all the vents are shut. It would cause problems it would seem to me.

I guess I could just run the two lines out toward the body with a restricted opening so it could breath ?

Maybe use some type of filter like hog hair ???

I blocked off the 2 other lines (vent & return) and drilled an 1/8" hole in the center of my gas caps, to vent my tanks. Has worked fine for over 20 thou miles.