I too have a 40 gallon onboard tank, and the 2nd year I owned it, even though I stabilized it, topped it off with new gas, and even put stabilizer in every time I put gas in the year before it ended up costing me $1200.00 to rebuild the carbs and get the tank cleaned out the first time I took it out. So now at the end of the season before I put mine away I drain the gas out of it, put a new filter in, and it sits empty until spring when I refill it with non-ethanol. I rigged an old 12 volt Hot Rod electric fuel pump, bought the motor end of the fuel line tap, plug them together, and pump the old fuel into my pickup. The last thing I want to do is worry about rotten gas in my tank.