Aux Tank Vent Line

[M36]

Im replacing a leaking aux fuel tank that has a crack in it where the bolt head is. PO, (Im 2nd owner) removed the vent hose going somewhere. When I replaced the main tank long time ago I think I capped off a vent hose on it. Maybe why I have fuel marks below the fuel caps.

If these go to a charcol canister it's gone. Any thoughts on trying to reinstall the vent hoses and where to, or just cap them off as before?

Pics of both tanks.

And, anyone know what these little goodies might be that came out of the fuel tank?

Never mind, just looked at the sending unit, came of the end.

 

[Farrell Martin]

The vent hoses should be open to allow air escape as you fill the tank. In my experience, when the vent hoses are blocked, gas spews out of the filler neck while i am filling up and my shoes fill up with gasoline. The vent hoses shpuld attach to a pipe near the top of the filler neck....I believe.

- F

 

[M36]

That is where the rubber hose goes to that is on the tank in the photo. There is a place for a smaller vent line that is plugged with the bolt on the old tank, but has a nipple on the tank Im putting in, for a smaller tube.

 

[JefeAZ]

I vented my tanks to each other. No filling issues yet. I ran the canister line to the front

 

[jrwyant]

Here's the auxiliary tank routing on a '77 bronco for reference, if that helps.

 

[DirtDonk]

Since your vapor/charcoal canister is gone too (too bad actually) then there's nothing really to do but to leave it plugged I would think.
Though there are some here that have made their own vapor release vent tubes going somewhere, so maybe they'll chime in and tell you what they did, but anything that vents fumes into the atmosphere is not necessarily a good thing if you park in an enclosed space.

I like the idea of connecting the two tanks together. Although I'm not quite sure why.?:? But it sounds like a reasonable bit of tinkering.

Some of us are actually getting later model charcoal canisters out of the junkyard or from sources like Summit, and retrofitting them to our trucks to keep the vapors out of the atmosphere and to keep an old rotting system intact and working to snuff. Not sure how a newer style gas cap works without the vapor recovery system, but I don't remember hearing of anyone having trouble leaving it off of a later Bronco either.

Paul

 

[M36]

Thank you for the info. BTW I fixed the crack in the tank with a soldering iron. I ran the hot tip down the length of the crack then folded the edge and some more plastic back into the track left by the iron. Then used it it to try and smooth out the repair. Fixed.