Question about 2005 Ducati Monster 1000S

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Gas Leak via Overflow

Been having an intermittent problem since an unfortunate parking lot tipover (grrrr!). Twice now, I've had gas flowing out the overflow tube, both times after filling up. The first time, I got it stop by opening the gas cap and "playing" with the tube. Yesterday, I lost about a gallon of gas, and kind of got it to stop by doing the same thing. Rode it home, and everything's OK. The tube attaches to the back of the gas tank. I wonder if it's a combination of the heat (weather), and the fact the tube may have been pulled too straight. Almost like the suction gets going, and it won't stop. I'll follow previous responses and look at the carbs and airbox to see if gas is coming out that way, but wanted to see what knowledge base I could tap. Not terribly mechanically inclined, so it can very well be something stupid (be gentle).

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The usual culprit is a blocked vent tube. Verify it's open. The usual indicator is either a pressure release when you open the gas cap, or a vacuum "sucking" noise when opening it first thing in the morning. On a carb equipped bike, the carb overflow lines will leak, but in a fuel injected bike like yours, it'll be out the overflow vent. The next time it begins leaking, open the gas cap. It should stop immediately as pressure inside is released. Good luck.

Posted on Nov 20, 2008

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