"Roger (K8RI)" wrote:

I can only give antidotal evidence, but I never drain the tanks in the
tractor, generator, snow blowers, lawn mowers...etc. Some of it ends
up in there for several years and I've never had mo gas go bad.

HOWEVER...When I shut down any one of them and know it will be for a
while, I do shut off the gas and let the thing run until the carb is
dry and the engine quits. If you leave the carb full of gas the stuff
will slowly evaporate over long periods and that will form "gunk". Gas
in my big generator may end up as old as two years. I turn on the gas,
give it time to fill the carb float bowl (just a few minutes) and it's
never failed to start.

Gum forms when fuel evaporates. If it can't evaporate I can't see how
it could form deposits. With the stuff still being good after two
years, I really don't believe it breaks down with age, or at least not
nearly as fast as some say.

Even back on the farm in "the old days" we never had problems with gas
going bad in storage or in the tractors over the winter.
We had both above and below ground storage.

This has been my experience.

Down here in the south (we probably don't have "winterizers"), you'd
have syrup coming out the fuel lines, or we used to. Dunno, I don't ever
let fuel sit that long anymore...

And thats been my experience...