(quoted from post at 09:13:48 09/28/14) Mike, ethanol is what many folks put in their gas tanks intentionally every winter to prevent fuel line freeze-ups, since the 1940's - it sold under the brand name of "Heet", amongst others. Possibly still does, but with alcohol now in most gas, in ordinary circumstances there is no need to add more. There is also "Iso-heet" based on isopropyl alcohol. Matter of fact, you may even seen alcohol fueled dragsters, with methanol in the mix.
Octane (gasoline) or Cetane (diesel fuel) and water separate. Most (if not all) alcohols are hydroscopic, meaning they absorb water. They also readily mix with oils, and burn, taking otherwise non-combustible water out of your fuel system a few drops at a time without making things run badly or stop. What a nifty idea.
There is a lot of money being made by hucksters selling 'snake oil' for all the ailments supposedly caused by ethanol in gasoline. Most of those problems are due to poorer quality materials put into fuel systems these days, not the ethanol itself. The biggest problem with ethanol, is the amount of energy that goes into making it (planting, harvesting, transporting, distilling) vs the lower 'work' value per gallon over gasoline. I noticed about a 6% reduction in fuel economy when E-10 was mandated, though I've also used E85 in my (non-e-85 rated) car without problems, other than even lower mpg.
Most tractor engines were built as low compression (~7.5:1), and will burn nearly anything that will ignite with a spark. IIRC, early gasoline had octane ratings in the 60's, not the 87+ we're accustomed to. Even the lack of methyl-ethyl lead isn't a problem, because lead was added as an anti-knock (burn control) compound for high compression (9.5+:1) engines. Ethanol works to a smaller degree the same as lead did, so it helps, rather than hinders.
Just my 2 cents.
Well Worn