Jim Wilkins wrote:

On Feb 1, 8:16 am, jim wrote:
Glenn Lyford wrote:
I've got two of those motors, and three carbs between them. The new
gas still manages to gum them up solid.

What new gas are you talking about?

I have been getting ethanol blended gasoline
at the local Farm Co-op since the 70's

And no it doesn't gum up carburetors
Quite the opposite it will clean out
gummed up gas tanks

-jim

I have a mid-1950's lawnmower with a 6BS engine and Pulsa-jet carb
that starts on the second or third pull in the spring even if I left
gas in it over the winter. The Gulf gas I buy hasn't turned foul-
smelling or gummed a carb yet (experiments, not normal practice).

It does cause black mold on the outside of the can.

One problem with leaving ethanol blended gas sit for long periods would
be the absorption of water. It will pick up moisture from the air.
Keeping it in a full air tight container helps prevent that.

It is not a good idea to leave an engine sit long enough so that all the
gasoline sitting in the carb evaporates. But that has nothing to do with
ethanol. If it were pure ethanol and it evaporated there would be
nothing left.

If the fuel has ethanol and is allowed to evaporate the ethanol and some
of the lighter end gasoline components will evaporate first. What you
have left is a much lower octane fuel with high boiling point (and
probably higher water content) that doesn't burn as well or as cleanly
as fresh fuel.


-jim



jsw