Pappy, I deal with a bunch of people in the marine industry, both wholesalers, and mechanics.There was a great article in the latest Outdoor Life regarding this new ethanol induced gasoline. It seems that after a few weeks, especially in the colder weather, the ethanol seperates from the gasoline, and then starts to gunk up. The question in the magazine was for marine engines, but holds true on any gasoline engine. Point is to use Stabil or similar product in all gasoline tanks or you may experience somr unpleasant results.
Ethanol doesn't separate, but it WILL dissolve water up to a point. When the water content suddenly gets too high, it falls out of solution, and that's what you see laying in the bottom of the tank.
Point is, personally, I think there was water in the tank to begin with, and there's condensation building up to the point where it suddenly becomes a problem.
Also, ethanol will loosen any dirt built up over the years, and if you suddenly go to a gasoline with ethanol in it, that crud will start coming loose and do all sorts of bad things.
Ethanol itself is a clear liquid - it has a freezing point of -114C (-173.2F), and it doesn't "gel" like gasoline or diesel fuel, it just turns solid.
So, if there's "gunk" in the tank, or a gel-like substance, it's more than likely something else going on.
And, for the record, here on Long Island, we've had ethanol in the gasoline for years. There have been cases where marine mechanics have found all sorts of crud and other things in the bottom of the tanks, carb bowls, filters, water-separators, etc. There was just no clear correlation between that happening and ethanol being introduced.
I do, however, wonder, if because of environmental regulations, that "stabilizer" is not the same thing as it used to be.