Prior to ethanol, it was a standard practice to leave untreated gasoline in your small equipment engines (lawn mowers, chain saws, generators etc) over the winter and they always started up like they should in the spring. Now its suddenly become "abuse" because we are forced to use that crappy ethanol ?? Now the standard is to treat the ethanol fuel with some type of additive so you wouldn't have carb or fuel line issues due to the corn squeezins. I go through Techron in the spring, and Stabil in the fall to treat the fuel.
I bought a 6500W generator at an estate auction this past spring. It was essentially brand new, no hours on it. The previous owner bought it 2 years ago, put some gas in it, ran it once to make sure it worked OK, and put it back in the garage. When I bought it, no gas in the tank, so I put some in and fired it up. Ran for about 1 minute, then quit. What happened is that he used ethanol gas (all you can get around here unless you go to the airport and pay Big Money), it evaporated out, and left a granular residue that looked like sand, and it really messed up the carburetor. Lesson learned.
Ethanol fuel exists today only because of mis-lead politicians in the EPA and the farm lobbyists. It isn't there on its own merits.