"Jay Honeck" wrote

Personally, I am skeptical that gasohol is going to harm my 1974-
vintage aircraft. I use the damn stuff in every other gasoline engine
I own, including my 1986 Goldwing, my 1995 Toyota, my 1995 Ford van,
my 1997 Subaru, my 2000 Mustang, my three lawn-mowers, my two yard
blowers, and my one snowblower -- ALL without problems.

But, hey, if the FAA says it's bad, I gotta believe 'em -- so I test
every tank for alcohol.

No doubt that you engine doesn't give a crap, but your fuel system could be
a different story.

I have seen pictures of fuel line swollen to the size of sausages, and who
knows what the other rubber parts (O-rings, fuel bladders, if you have them)
would look like, and how much alcohol it would take to get it to swell.

I think you are wise to keep on testing. If it were me, I would want to
know if the seltzer test worked as reliably as the add water test, and how
the seltzer would work on a fresh batch of alcohol.

Perhaps you can catch the gas tanker starting to fill a station's tanks, and
get a sample of gasohol right off the tanker, where it is less likely to
have gotten mixed with water, from storage tanks.
--
Jim in NC