The oxygen tends to lean the mixture entering the engine.

why do you think that? ethanol has a different fuel/air mixture ratio than
gas/air, so needs different jets.

No
matter what carb setting you apply after that, the air/fuel ratio never gets
back to what it was.

race engines did it for years.

Part of problem is that the gas formula isn't consistent across the country.
Non attainment areas have a different formula than say, rural Nebraska. The
Atlantic coast might have yet another regional formula. A production item
such as a carbureted outboard or inboard marine engine is a "one size fits
all applications" product. It works great in some areas and not so great in
others. Since those carbs are designed for an average gas formula (or for
whatever standard the engineers has chosen) it is impossible to set them
optimum when the gas supply is different from that original standard.

My comments are aimed at productions engines rather than something more
custom such as a race engine. I have seen rejetting offered as a
manufacture's solution in the past but don't recall seeing that recently. A
person could experiment with the jets try to get an improvement. With the
stalling problem, such as what the original poster had, rejetting might not
cure that problem. Those low speed circuits are partially controlled by the
size of drilled passageways, not something readily adjustable.


"JAXAshby" wrote in message
...
The oxygen tends to lean the mixture entering the engine.

why do you think that? ethanol has a different fuel/air mixture ratio
than
gas/air, so needs different jets.

No
matter what carb setting you apply after that, the air/fuel ratio never
gets
back to what it was.

race engines did it for years.