News:

Howdy, Com-Pac'ers!
Hope you'll find the Forum to be both a good resource and
a place to make sailing friends.
Jump on in and have fun, folks! :)
- CaptK, Crewdog Barque, and your friendly CPYOA Moderators

Main Menu

Fuel Mileage for sailpro 6hp.

Started by waterwheels, July 26, 2015, 09:33:37 AM

Previous topic - Next topic

waterwheels

I am not formilar with E-10 but assume it is an ethanol blend. I use high octane supreme unleaded 91-93 octane in all my small engines.

There were a few lakes I could have sailed for an hour or two but the wind seemed to always be on the nose so I didn't bother on this trip.

Don

skip1930

#16
Pushing against the wind and waves ... no way to tell how much ground will be covered.

Beats me ... When the tank gets close to empty, I fill it up again. I know I can drive her twenty six miles with a 5 hp two cycle on way less than my three and a half gallon tank at a comfortable rpm.

But the 6 hp will burn X amount of gas per hour.

Here is some insight to 'X'.


OUTBOARD GAS CONSUMPTION



For years, we computed outboard gas consumption easily. While there were a few differences, most outboards burned gas according to the following formula:

Gas consumption per hour= horsepower/10
A 40 hp motor would burn 4 gallons per hour.
A 20 ph would burn ______ gallons per hour.
A 9.9 hp would burn _______ gallons per hour.
A 90 hp would burn _______ gallons per hour.

Outboard Gas Consumption


But nowadays, there is great difference among motors. Some brands of 2 cycle engines burn fuel by the formula:
Gas consumption per hour= horsepower/12
Four cycle engines are now boasting of even better gas consumption. Many burn gas according to the formula:

Gas consumption per hour= horsepower/15.

Using the above formula of:

Gas consumption per hour= horsepower/15,

how much gasoline would an engine burn with the following horse-power and given time of operation?

a 40 ph for 4 hours?
A 25 hp for 3 hours?
A 90 hp for 6 hours?
A 6 hp for 9 hours?

Write the formula for your family's outboard motor gas consumption.
In each case we assume that the engine is being run full throttle.

Doesn't read like this is too much help.

But 5 over 10 is 0.5 with two cycle. And 5 over 15 is 0.3 with four cycle ... well yea.
But the two cycle makes power with every trip the piston makes up the bore.
While the four cycle makes power only on every forth trip up the bore ... hence burns less fuel. Just a guess.

Begs the question ... can we develop the same power with a two cycle with less rpm?

Sorry skip.




hoddinr

Did you make it all the way from Kingston to Ottowah? How long were you gone?

Thanks,
Ron

waterwheels

Ron,

We took our time and made a side trip up the Tay Canal into Perth for two days. We went from Kingston to Merrickville and back to Kingston. We spent 14 nights on the boat with a total of 184 miles.

I have some pictures on FB if you want to PM me I will give you my info.

Don