Ducati Monster Forum

Moto Board => Tech => Topic started by: powerband on May 27, 2009, 09:50:45 PM

Title: HELP: Gas Coming out of Gas Cap (???)
Post by: powerband on May 27, 2009, 09:50:45 PM
After a hard ride over the weekend, I have been smelling gas in the garage where I park the M620.  I checked around and discovered that gasoline was coming up the tank (currently about half full) and out of the gas cap.  WTF.  It's almost as if there is pressure in the tank.  What  could be causing gas to work its way up the tank and out the gas cap?

Help! 

Thanks in advance.
Title: Re: HELP: Gas Coming out of Gas Cap (???)
Post by: Popeye the Sailor on May 27, 2009, 10:00:44 PM
The gas, no doubt sensing the impending doom of the oncoming apocalypse, is attempting to escape to freedom that it may escape the oncoming onslaught. Woe to all.


Or your gas tank is not venting properly, and what with gas expanding as it gets warm, is causing this. I'm not 100% sure where that vent is though. Hopefully someone will chime in.
Title: Re: HELP: Gas Coming out of Gas Cap (???)
Post by: powerband on May 27, 2009, 10:04:40 PM
Of note is that the bike has been parked this whole time while the gas is seeping out of the gas cap.   ???

In the meantime, should I keep the cap slightly ajar? 

Thanks.
Title: Re: HELP: Gas Coming out of Gas Cap (???)
Post by: Howie on May 28, 2009, 04:19:06 AM
Is there positive pressure when you open the cap?  Is the gasoline coming out the little vent hole in the cap or from around a gasket?  Which one?
Title: Re: HELP: Gas Coming out of Gas Cap (???)
Post by: powerband on May 28, 2009, 08:29:31 AM
I am not sure exactly where the gas is coming out of because over night I had the gas cap slightly ajar.  It dawned on me, though, that it might not be coming out of the tank itself, but from the overfill hole (?).  Is this possible?  I'm thinking it might be coming from the vent hole right under the gas cap, above the entrance of the tank.  THoughts?
Title: Re: HELP: Gas Coming out of Gas Cap (???)
Post by: ducpainter on May 28, 2009, 08:37:34 AM
Quote from: powerband on May 28, 2009, 08:29:31 AM
I am not sure exactly where the gas is coming out of because over night I had the gas cap slightly ajar.  It dawned on me, though, that it might not be coming out of the tank itself, but from the overfill hole (?).  Is this possible?  I'm thinking it might be coming from the vent hole right under the gas cap, above the entrance of the tank.  THoughts?
If it's doing that it should also be going into your charcoal canister, if you still have one, or on the ground.

If the hose that connects the tube inside the tank to the cap holder splits, this can happen.
Title: Re: HELP: Gas Coming out of Gas Cap (???)
Post by: powerband on May 30, 2009, 11:56:05 AM
I haven't been able to do much to the problem, but what I discovered was that this overflow is happening intermittently.  The gas cap neck is dry at certain points and filled at others.  Any thoughts on this strange occurrent?