dpb wrote:

Pete C. wrote:
Murriel wrote:
...
Now I see that the gasoline at the staion where I deal has 10%
ethanol. Is this acceptable for lawn mowers and garden tractors?

Not really, ...

From B&S FAQ--

All 4 stroke cycle spark ignited engines

Fuel must meet these requirements:
* Clean, fresh, unleaded gasoline.
* A minimum of 87 octane/ 87 AKI (91 RON). ...
* Gasoline with up to 10% ethanol (gasohol) or up to 15% MTBE
(methyl tertiary butyl ether), is acceptable.

For current products. Many of us run products that are a decade or more
old.


Except as noted earlier for older engines since ethanol is widespread
and in some areas mandated, it would be most surprising if the engine
manufacturers weren't building their engines to run on the available
fuels. (They aren't variable-fuel systems, though, so E85 is out since
they require new carburation, etc..)

There is also a difference between "run on" and operate reliably over
time with.


While B&S does recommend adding fuel stabilizer to ensure fuel doesn't
get stale since most homeowners don't use fuel very rapidly, I'm
convinced that's an avoidance policy to attempt to minimize customer
complaints rather than a real need. If a little additive can all of a
sudden make fuel perfectly fine for 24 months, it would be quite
remarkable the fuel itself as manufactured isn't able to last even 10%
of that time span.

I've been storing fairly large quantities of gasoline for 1yr+ for years
and I can definitely tell you that Sta-Bil makes a huge difference. I
can also tell you that since we started getting alcoholic fuel it's
storage ability without Sta-Bil has decreased dramatically over the
non-alcoholic fuel without Sta-Bil. I don't yet have a solid
determination if Sta-Bil can keep the alcoholic fuel good as long as it
can the non-alcoholic fuel.


I've routinely let equipment over-winter w/o any special treatment and
never in 40+ years had any issues the following year/spring/summer.

In 25+ years I've had a number of items with issues in the spring after
being stored over winters and in every case it was stored with untreated
fuel.


I just took an old B&S on a tiller that hadn't been touched for 10 years
and the gas left in that tank was not as some might have one believe,
gel nor were there any significant deposits, etc.

Probably had Sta-Bil or similar added then, since I've seen equipment
left a mere two years with nasty sour fuel in the tank.

Dump the contents of
the tank and rinse it out, put a little carb cleaner through the jets, a
new plug and little thin oil in the cylinder and spin it a few times to
lube it up a little. After that it started on about the third or fourth
pull and runs just fine, thank you very much...

The lore is far overblown from the realities in my estimation and
according to my experience.

Not in my estimation nor experience.

PS: An ultrasonic cleaner full of warm Simple Green works wonders for
reviving a carb that's gunked up.