Fuel mileage idling down a river

[MARVIN OR JANNET POLSTON]

I'm thinking about taking a trip down the river and I'll mostly be going in a fast idle with the current does anyone know about what the fuel mileage would be, I have a 92 270 da Sundancer with a 7.4 Mercruiser carburetor,

 

[paulswagelock]

6 gallon per hour at 2000 rpm
3.5 gallon per hour at 1500 rpm.

You need to know your speed at those rpm for mpg.

 

[MARVIN OR JANNET POLSTON]

6 gallon per hour at 2000 rpm
3.5 gallon per hour at 1500 rpm.

You need to know your speed at those rpm for mpg.

Thank you for that answer, maybe 6 mile a hour

 

[paulswagelock]

So between 1 and 2 mpg, rounding.

 

[JNorgren]

That is what I get at those rpm's
1500 RPM, 6 MPH, 3.5 GPH @2.3 MPG
2000 RPM, 8.3 MPH, 6 GPH @1.6 MPG
Good Luck and enjoy your yacht....

 

[scoflaw]

Speed of the current also a factor.

 

[Creekwood]

I'm thinking about taking a trip down the river and I'll mostly be going in a fast idle with the current does anyone know about what the fuel mileage would be, I have a 92 270 da Sundancer with a 7.4 Mercruiser carburetor,

Curious why you would be concerned with that? A full tank of gas is many many hours at idle or just above idle speed.

 

[PMC]

Curious why you would be concerned with that? A full tank of gas is many many hours at idle or just above idle speed.

To get those dead beat friends to kick in some cash of course!!

In all seriousness, I'm curious of the answer as well. I'd hate to learn that the OP is fueling up ONLY for this trip (and short 5 gallons due to environmental conditions).