Vent tube gas leak

[Al in Arkansas]

Gassed up earlier. Parked shortly after.  Cme back to find a circle 10" in diameter on the pavement where gas is coming out the vent tube.  Pulled tank and gas is spewing from the vent tube, even though the tank is on its nose. Suggestions?

Al

[R J]

When I happen to pack it in too tight, if I don't ride any distance and park, it will leak, due to being over full.

Why did you pull the tank?

[donaldcc]

When I happen to pack it in too tight, if I don't ride any distance and park, it will leak, due to being over full.

Why did you pull the tank?

  In the summer here in the desert when it is very hot the vent tube is fuming with vapors coming out and a little drip spot beneath the tube.  This happens even if I am not filled up.  I would say normal when you fill to top and park right away.

[wild6]

Vent tube ends in the top nose of the tank (highest point when mounted), so if you have it on its nose, the vapor pressure building in the tank will force gas through and out the tube.

You may have just filled it too much and if the tee on the vent line is clogged (or missing), it could have started a syphon.

Sure it was the vent that was leaking and not just a leaky carb drain?

[Al in Arkansas]

It was definitely the vent tube.  Pulled the tank to get a better look at everything.  It was actually leaking where the vent tube connects to the T about half way down the vent tube.  That tube was a little cracked.  Something about being 12 years old I guess.  Replaced that section of the tube and rode home.  Wondering if that T is plugged.  Plan to pull it next week and look closer. 

Thanks - Al

[conzz]

I have the same problem - slow leak from tank vent tube. It only happens when in extreme heat like we're having in NWA now and the bike's sitting in the hot sun. If I pop the gas cap open, it stops. Any ideas?

[BF]

Probably just filled it up too much.  I wouldn't worry about it. 

But on the other hand, do you have any rust in your tank?  The vent tube could be rusted enough to allow gas to enter it.  Pulled your petcock lately?  What's the filter screen look like?

[hubcapsc]

Pulled tank and gas is spewing from the vent tube, even though the tank is on its nose.

Probably unrelated to the leak you saw before you pulled the tank?

The first time I pulled my tank it was in the winter. It was the last thing I did that day, set the tank
outside, on its nose.

When I returned the next morning a siphon action had started (I think you're supposed to hold
your finger over the vent tube when you turn the tank on its nose to prevent the siphon action
from starting...) and there was a frozen fountain of gas coming out of the vent tube  ...

What everyone else is saying about heat and full tanks and the cracked hose you found at
the tee is probably what caused the gas leakage you saw before you pulled the tank...

Daniel Meyer was talking about how important that tee is, and the lines that are hooked to it,
one of the times that I walked past the tech-demo at InZane, so when you fix the cracked hose,
try to hook everything back like it is supposed to be... I think the line on one side of the tee
goes to nothing, it acts as some kind of siphon break, someone will probably say more about it...

-Mike