If my tractor is not used for a few weeks, I notice that some of the gas has disappeared. When it sits idle for the winter months, the tank will be empty of gas, but I think it still contains water because I had a problem with water in the gas the first time I used it this Spring. It sits in my enclosed garage and I do not notice the smell of gas or see signs of a gas leak. The cork seal in the tank cap is dried up. Is it possible that the gas is evaporating thru the top of the tank? It seems that if I had a very slow tank leak, the water in the tank would also be leaked out also when Springtime arrived.