There are a lot of fuel treatment products available now to deal with ethanol based fuels. Walk into any Autozone or other auto parts store and you would probably have about a dozen different options. Gold Eagle, maker of STA-BIL products, makes a good ethanol treatment for use in all vehicles, including small engines. Here is their site page for this product:
Ethanol Treatment
Here is also a pretty good FAQ section on their website that explains more about ethanol based fuels and treatments for it. Hope this helps!
FAQ's
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