I'm not sure I understand what you wrote. Does that mean my 2-stroke 250
outboard should be burning 25 gallons per hour at full throttle. That
doesn't sound right. Can you restate your formula in English?

--

Yes, you're correct. The general rule of thumb for a two stroke
carbureted outboards is 10% of horse power per hour at WOT. So a 25 HP
would be 2.5 GPH at WOT. A 115 HP would be 11.5 GPH at WOT. So it
stands to reason a 250 HP would be 25 GPH at WOT. It is just a rule of
thumb not exact. I have also read that another rule of thumb people use
is 1.2 GPH per 10 HP. That calculation is actually a little higher than
the one I use.


Paul