As a fellow mogas flyer who burn over a thousand gallon of mogas a
year in my plane, and believing the aviation industry is stupid not
moving away from engines requiring 100LL (they should only install
gasoline engines requiring 91/96 or lower octane, or aero diesel
engines into new production planes, if you ask me), I do believe that
mogas deteriorates faster than avgas. The reason is probably due to
different chemical make-up btween mogas and avgas. Mogas's end
distillate is slightly heavier, meaning it has more larger hydrocarbon
molecules in the mix compared to avgas. It also contains a higher
percentage of aromatics hydrocarbon. Those chemical property of
mogas, when oxidized over a long period of time, tend to make the fuel
off-spec more quickly than 100LL.

http://www.generalaviationnews.com/e...olumn&-nothing

Look at the brighter side Jay. If we're paying $1.50/gal less in
fuel, a good chunk of our flying is free. We should simply go fly
more often.


On Sep 15, 1:45 pm, Jay Honeck wrote:

You know, I've heard that ever since I started using mogas in my
planes, but I've never seen a cite, nor have I *ever* noticed a
problem with unleaded gasoline in *any* of my lawn mowers, leaf
blowers, or snow blowers.

I put 'em away in the spring/winter, and start 'em up the following
winter/summer -- and away we go. Same with my Honda Goldwing -- I
top
it off, and it just sits till next year. No troubles.

Can anyone point me to anything that proves (or disproves) the "fact"
that unleaded mogas deteriorates faster than avgas?