My portable emergency generator has about 5 gal of gas in it’s 9 gal. tank, and I am uncertain how to best prepare it for the next time of use. Whenever I shut the engine down, I close the valve and run the carburetor out of fuel. I am undecided which is the best method of storage for the generator. Should I add the appropriate mixture of Stabil and top the tank off? Should I just add enough Stabil for the current 5 gal of gas? Should I drain all the fuel from the tank and just add fresh gas the next time I need the generator? If I leave gas in the tank, I would crank the generator and let it run for a few minutes every month or so.