Speed and fuel range

[Algis]

I just purchased a 205 Hunter 27 with a yanmar 2GM-20F engine. I plan to motor the boat from St. Louis Mo. to Chicago, IL.

I need to get an idea of cruising speed and fuel consumption to plan my trip.

Thanks,

AL

 

[Les]

I have a 2008 Hunter 27--so we have the same hull. I also have a Yanmar 2YM15 so I cannot give you a specific answer. However, the waterline length of our boat is 23'7". The square root of that is about (I'm not good at math) 4.8 which give me 23.04, close enough for jazz. So we take 4.8 X 1.25 which should give us 6 or your theoretical hull speed. On my boat that is what i get with a clean bottom--about six knots under power.

I suspect our engines are close enough in power output to be similar in nature and I get about a half gallon per hour at 3000 rpm. You have a ten gallon fuel tank so I estimate that you will use four gallons in an eight hour day. I'd fuel up every day as I don't like to go under half a tank.

I have no idea of what types of currents you will get, never sailed on a river before. Best of luck. Let us know how you do getting to Chicago.

 

[Steve Dion]

Al: I don't know much about the river currents in that part of the world, but I think you may be facing some strong currents depending on when you are traveling. I would plan on a little more fuel consumption if you are running into the current for that trip. If you only have a 10 gal. tank I suggest that you pack another 5 gals. with you.

What is the approx. distance of the trip?

 

[Jon Bastien]

I have a 2GM20F in my H290, and at cruising RPM (~2300) it burns a little less than half a gallon of fuel per hour.

The numbers: With the boat (14k lbs), heavily loaded (add 3k lbs), crossing the Gulf of Mexico (no current to speak of) in NO wind (thus no sailing or motorsailing), we calculated the burn rate at .42 Gallons/hr with an average speed of 5.5 knots.

You, of course, will need to factor the current working against you for the majority of the trip. The 'gallons per hour' won't change much, but the 'miles per gallon' and 'miles per hour' certainly will.

Good luck with your trip! I'll be headed along that stretch in the other direction sometime next year, as part of the Great Loop. I'm looking forward to spending some time there.

 

[Algis]

Distance

Al: I don't know much about the river currents in that part of the world, but I think you may be facing some strong currents depending on when you are traveling. I would plan on a little more fuel consumption if you are running into the current for that trip. If you only have a 10 gal. tank I suggest that you pack another 5 gals. with you.

What is the approx. distance of the trip?

The distance from St. Louis to Chicago is 370 miles. I belive I have a 15 gal tank but plan to carry an extra 5 anyway.

 

[navigator97]

On my 2GM20F Yanmar engine (on a Hunter 33.5) I range fro 0.28 GPH with a new mixing elbow to about 0.47 GPH when the mixing elbow need changong. On average I use 0.40 GPH for trip planning. Using your trip distance and 5.5 Kts, you will be motoring about 67.3 Hrs.and consume about 26.9 Gal. of Diesel. For safety margin you should plan on having 40 Gal. available one way or the other. Either fuel stops or extra fuel jugs.

 

[Benny17441]

The speed is controlled by the throtle setting, hull condition, wind and currents strength and direction. Fuel consumption is mainly a factor of engine size. A 2GM has a burn rate of close to 1/2 gallon per hour (GPH). The specs on the 27 indicate a fuel tank of 12 gallons. Not all of them are usable, a 2 gallon reserve for emergency and to prevent the engine from sucking air would be necessary. So you may base your figures on 10 usable gallons which should render approximately 20 hours of motoring. If you can move at an average speed of 4.5 knots the boat will have a range of approximately 90 nm. The tires of an automobile are mechanically engaged to the road so fuel consumption can be related to miles travelled but in a boat the road is a fluid and there is induced drag and slipage so the way to measure fuel usage is by calculating fuel usage in a unit of time. We run a 2GM on an h320 and our burn rate is a tad short (85%) of 1/2 GPH which renders that figure as a safe factor to conduct our calculations. You can more precisely calculate your burn rate by keeping a simple log of gallons used as indicated by the pump when the tank is topped off over time as obtained from an hourmeter or a clock. Your average, which will consist of your average throtle settings will be a more tailored figure to your use. If you motor sail you can extend the range but if you have to beat against weather then your range will be shortened. You may carry another 10 gallons of fuel in jerry-cans tied up on deck to double your engine run time.

 

[Stu Jackson]

Benny and the others are right. But if I was you, I'd carefully research where ALL the fuel docks are on your course, and what their opening hours are.

The Great Loop website may have that information. If not, try Active Captain.

Have a great trip.

 

[Sailm8]

Be sure to factor in the current. This link http://www.nps.gov/miss/riverfacts.htm says to expect 1.5 mph at the headwaters and 3 mph at New Orleans. I would expect to average 3-4 knots against the current.

 

[MrSteve007]

I was just looking over my fuel log for my 2002 326 (with a stock 2GM-20F, 340 hours). At a cruising rpm of 2,600, I get a 0.26 gallons per hour of consumption, and a speed of about 5 knots. At 3,100 rpm, I get 0.38 gallons per hour of fuel burn, and 6 knots of speed across the water. This is with the stock prop, clean hull.

 

[Dan Hill]

Last year we made a 330 mile trip up the hudson river and through the eire canal. We burned 19 gallons diesel cruising our hunter 28.5/2gm20f @ 4.5 knots. Math tells you we got just over 17mpg. But this does not take into account any currents, good or bad.