Fuel vent (i think) question

[guidoverduci]

I’ve got a non-efi aftermarket 23 gal fuel tank. After filling it up, I noticed fuel dripping out out of a 5/16 line that’s all the way to the left on the tank. I still ended up driving hit home, but when I pulled in the driveway it was spewing out pretty bad. It was a leaky hose. I replaced, no more leak. The rubber line is about 6 inches, then attaches to a hard line. It runs up and around a few things eventually ending up into my air filter. So I’m guessing some sort of vent setup. I also have a carter electric fuel pump with this setup.

So, I just want to make sure this is correct. If I slightly overfill this tank, fuel vents out that line. When I pulled the bad line, fuel dribbled out a bit, but then stopped. I had a cap on it for about 10-15 minutes while I swapped in a new line. When I pulled the cap off to slide the new line on, fuel spewed out pretty quickly, as if the pressure built in a short amount of time. Does all this sound normal, could enough pressure build on a full tank to run fuel all the way to the air filter?? I doubt it, there are some big bends and wrap arounds till it gets to the filter, but someone smarter than me can chime in! Thanks!

 

[spap]

It s the evap system goes through the charcoal canister mine does the same thing
I need to get the vent line higher than the tank so it won’t do that or just don’t fill it to the top

 

[guidoverduci]

It s the evap system goes through the charcoal canister mine does the same thing
I need to get the vent line higher than the tank so it won’t do that or just don’t fill it to the top

I see. I don’t have any of that original equipment, but it sounds like that’s probably what it used to go too. Yep, probably just won’t fill it that high.. but at least that leak is fixed!

 

[needsmoarturbo]

Yes as mentioned above that should go to a charcoal canister and then from the canister to the intake to be burned up by the engine. This is to keep fumes from escaping to the environment. I think newer engines have check valves and solenoids involved as well that regulate flow from the canister to the engine, but not sure how the old original one was set up.
I'm sure a lot of guys just block those ports off, bit if you have some sort of canister setup it will help keep your garage from smelling like an old truck.

 

[spap]

Yea it goes across on the metal line to the pass side of the truck mine leaks from the check valve in the middle of the truck then to the char canister Diff don’t want to block it off it will stink. Fill it up and drive fast at 12 miles to the gallon it goes down quick haaa

 

[guidoverduci]

Yea it goes across on the metal line to the pass side of the truck mine leaks from the check valve in the middle of the truck then to the char canister Diff don’t want to block it off it will stink. Fill it up and drive fast at 12 miles to the gallon it goes down quick haaa

12! I’m probably in the single digits!

 

[spap]

Around the block haaa