Fuel mileage

[sully]

I just bought a 17.5 ft aluminum boat with a 100hp yamaha 4 stroke. It has a 12 gallon tank but the gas hand dont work. Im use to big bass boats that hold plenty of gas and was wondering if anyone has an estimate of how many miles i can get out of 12 gallons?

 

[Guest]

Well I tell you this. I went from sullivans boat ramp to the dam and back on 15 gallon about a 70 mile round trip. I have a 115 on a 18.5ft boat.

 

[ChooChooSnakeMan]

sully - 2/23/2022 5:54 AM

I just bought a 17.5 ft aluminum boat with a 100hp yamaha 4 stroke. It has a 12 gallon tank but the gas hand dont work. Im use to big bass boats that hold plenty of gas and was wondering if anyone has an estimate of how many miles i can get out of 12 gallons?

Most mid range outboards on light aluminum boats are going to get I would think around 6 to 7 miles per gallon at your most efficient cruise rpm. That range is usually between 3000 to 4000 rpm. My Lowe 17' tin with a 90 hp opti 2 stroke does very well at cruise speeds. I can run about 30 mph at 4000 rpm and 10 gallons of fuel will take me a long way.

 

[WaterChap]

The standard formula is 1/12 of a pound of fuel per hour per unit of horsepower at cruising speed. Your light boat and four stroke will help. Gas is 6 pounds a gallon. You’ll burn 8.33 gal per hour. So if your cruising speed is 25 you’re getting 3 miles to the gallon. Any error would be in your favor so I’d expect 3-5 miles per gallon and maybe higher if your cruising speed is above 25.