SmallBoats.com wrote:
Without a guage, I need suggestions as to how to estimate my gph use
on a small skiff. I could fill the tank and run around all day, but is
there a better way?


Fill a six gallon tank. Run the outboard at a constant speed for an
hour. Fill the tank again. Note how much gas you burned. That's your
approximate GPH at that speed with the load you have in the boat at the
wave, wind and temp conditions you experienced.

If you vary the speed over the hour between idle, trolling, cruise, and
WOT, you can fudge an "average" GPH, as Tom and some others do. It's not
accurate, but it's fun.

A rough formula for a gasoline outboard is to divide its HP by 10. The
resulting number is the approximate GPH at WOT. With my Yamahas, I have
found that number to be a little high, but close enough for private
corporate work.