Gas syphoning out the vent/tank problems

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no1newb

no1newb

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Hey guys, been a LONG time since I've been on here, but need to get comfortable with my car again.

I had my car worked on a year or so ago, and had a couple issues when I last got it out, and hate to say it but it's been sitting in the garage for too long now.

Initially taking her out, I ran out of gas pretty quick, and died in town, next time I took it out, I went straight to the gas station. And at the pump, fuel just started spitting out the vent tube. Stopped pumping, and it kept going and spit out a few gallons right onto my exhaust...

Taking a look, the fuel tank and vent tube, it looks like the proper factory setup. I ran a camera into the fuel tank, and it seems like it's about half full or less (I'm also having weird gas issues like it's not making it to the carb, so kinda wondering if my fuel tank/car stance is making the fuel sit in the back of the tank.).

Anyway, the syphoning probkem... looking in the fuel filler tube, it looks like the vent section has a splash guard or something going down the length of the tube. I'm wondering if... Somehow, the vent is syphoning gas all the way down in the tank, because the filler tube vent section is gummed up maybe? Combined with the gas tank probably not laying as level as original, causing me to not be able to fill my gas tank up more than a few gallons...

Thoughts/ideas? Does this make sense? It doesn't seem like this is a common problem that I can find, and I can't for the life of me understand how it could be syphoning so much, with the vent tube being at the top of the filler tube
 
Sounds like it is not venting. You must confirm that it is venting by blowing air from the exit back into the tank.
 
Maybe you had the nozzle pointing right at the vent tube opening forcing it out. If the gas cap was off.......It's vented.
 
66Vcuda said:
Check the filler neck to tank rubber grommet and the sending unit to gas line rubber connection.
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That looks clean, I think the guy who did work on my car before replaced the rubbers on that. The sending unit looks okay too.
CFD244 said:
Maybe you had the nozzle pointing right at the vent tube opening forcing it out. If the gas cap was off.......It's vented.
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Yeah, I think that could have started the syphon effect initially, but it kept spewing out gas for a good 5 minutes or longer after I stopped the pump. Hell, it was still piss'n gas when I got it home. (Had it towed as I panic'd once gas started going o. The exhaust) honestly, think it probably would have stopped if I put the cap back on right away. I got the proper factory gas cap after this to make sure I could get a good seal.
Murray said:
Sounds like it is not venting. You must confirm that it is venting by blowing air from the exit back into the tank.
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If gas is coming out the vent, the line itself isnt clogged right? Not understanding how that'd help
 
I'm thinking like 66Vcuda. I think it is actually a leak. I've had them from 3 different spots.

1. Gas filler tube grommet to tank.
2. fuel sender lock/o-ring.
3.Fuel sender to rubber gas line.

Any of those can leak bad enough to keep you to around half a tank if sitting long enough.
 
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Someplace, over at slantsix.org? There is an article on the early vents. The Barracudas (is that what you have??) Are somewhat different than the "trunked" cars

Is it possible the vent has been re-worked? The way the stock Darts / Valiants are built, it would be near impossible to spit, unless the tank is absolutely full up in the filler neck, and the inverted U of the vent is to break siphon

WHEN YOU POSE A QUESTION, please post year make and model
 
67Dart273 said:
Someplace, over at slantsix.org? There is an article on the early vents. The Barracudas (is that what you have??) Are somewhat different than the "trunked" cars

Is it possible the vent has been re-worked? The way the stock Darts / Valiants are built, it would be near impossible to spit, unless the tank is absolutely full up in the filler neck, and the inverted U of the vent is to break siphon

WHEN YOU POSE A QUESTION, please post year make and model
Click to expand...
My bad, it's been a while

1965 Barracuda, running a 318 the previous owner put in.

The vent to me looks original unless he ran something different inside the filler tube, but I can't imagine that.

When it happened, I was able to stop it by plugging the vent tube with my finger, so I know it is coming from there and not a leak.

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Does the vent run down the whole filler tube, without any gaps to breath? The more I'm thinking about it, it seems like once I got the tank filled to the base of the filler/vent tube, it can syphon out the top part of the tank
 
The vent line starts at the top of the filler tube as you've shown and exits the trunk pan near the gas tank and that end is open. I see you have a new sender, it might have an extra nipple for fuel return. Maybe the P.O. connected your vent line to the sender there? Just guessing at this point now.
 
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I couldn't get a good picture of it, but it didn't have the extra return nipple. it's just running the single 5/16 out, Had a better view with a snake camera, and wanted to make sure (been thinking about switching to the larger diameter line, and adding a return for vapor, as I've had problems with vapor lock before a long time ago)
 
Hi i think your filler tube needs turned so the vent line is straight up,as for the other problems it might be time for a new gas tank
 
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