How do fuel tanks vent?

[redcali]

Truck been sitting 10 years. Gonna start her up soon. When I put fuel in the tanks, it seemed to gurgle in slowly and then actually spit some back out (both tanks). Is there a vent or something that may be clogged? Thanks for any advice.....

 

[SeaBiscuit68]

What year is your truck? The early ones only vent through the cap and can be troublesome to fill. My '68 required the nozzle to be at 8:00 to spiral the gas down the neck avoiding the vent tube. Poke your nose under there and you can see the tube and where it attaches to the filler neck.

 

[blazinchuck]

just a thought, but does it help if you fill the rear and have the front cap removed? there should be the canister between both tanks, maybe messed up,Chuck

 

[Broncobowsher]

just a thought, but does it help if you fill the rear and have the front cap removed? there should be the canister between both tanks, maybe messed up,Chuck

From the factory (major caveat when dealing with broncos) there is nothing connecting the 2 tanks that will make them vent any differently when filling them.

It's the nature of the beast. decent fuel tank recirculation plumbing doesn't exist. It ain't a new car. Ever try and fill a '67 mustang at a pump? got to get those just right as well, and they only have a few inches of filler neck.

Advances in modern fuel tank filler neck design are wonderful, until you need to fill something old and realize where we came from.

 

[SaddleUp]

Nature of the beast. Even with the vent tubes they are a pain to get filled. 9 times out of 10 I just need to stand there and hold the nozzle to get mine to take fuel and it has a vent tube.

 

[JaxLax]

i used to turn the nozzle upside down

used to work pretty well

now that prices are what they are it's no longer pump til it's full....

 

[66halfdone]

It might be time to drop and clean those tanks. Mine sat for only 3 years
and I could not believe the stuff that was in there. The PO had all kinds
of fuel issues and it was no trouble figuring out why.

 

[SaddleUp]

Mine better not be very dirty inside. It's only been in a little better than a year now.

 

[musetech]

Vents from a 3/8 hose plumbed from the tank back up to the neck. I know my main 1 1/2 or whatever main hose is kinked a little just before it goes into the tank and likes to spit back from there.

Still have to pull the vapor recovery deal back on the nozzle and aim it just right to find the sweet spot. That nozzle clicks off once after 19 gallons and I call it good. 23 gal tank.

 

[Broncobowsher]

Vents from a 3/8 hose plumbed from the tank back up to the neck. I know my main 1 1/2 or whatever main hose is kinked a little just before it goes into the tank and likes to spit back from there.

Still have to pull the vapor recovery deal back on the nozzle and aim it just right to find the sweet spot. That nozzle clicks off once after 19 gallons and I call it good. 23 gal tank.

Some of the newer Broncos have a 5/8 vent hose going up to the filler neck. My ’69 has one on the main tank, but not the aux.
That hose helps, but by no means is a cure.

 

[302fix]

Truck been sitting 10 years. Gonna start her up soon. When I put fuel in the tanks, it seemed to gurgle in slowly and then actually spit some back out (both tanks). Is there a vent or something that may be clogged? Thanks for any advice.....

If it's been 10 years and has had any gas in the tank, I'd suggest a new tank or at least getting it professionally cleaned. The shelf life on gas is about 3 months and in 10 years it will turn to goop.