Fuel consumption

[ChrisE]

Hilda Maud is a 23' Orkney Orcadian and is powered by a 115 4 stroke Yam o/b. I seem to be getting about 15l/hour fuel consumption with revs in 4300 range.

 

Is this about right?

 

Thanks for any input.

 

Chris

[Rob]

 

How fast is that? 4300 means nothing unless you translate that to speed- then work on litres per mile.

 

Imagine woudl be a good comparison (Paul F's Orkney 20 with Yam 80)

 

Rob

[TomBettle]

Hilda Maud is a 23' Orkney Orcadian and is powered by a 115 4 stroke Yam o/b. I seem to be getting about 15l/hour fuel consumption with revs in 4300 range.

 

Is this about right?

 

Thanks for any input.

 

Chris

Chris

 

That sounds about spot on. Possibly slightly optimistic as I used to work on about 20l/h at 4000 rpm on a Suzuki 140Hp 4s which was the same block.

 

Tom

[ChrisE]

Thanks both.

 

4300 gets us about 12-13 knots with a well cleaned bottom. So in l/m, just under 1.

 

Chris

[Sinbad]

My cruising speed is slightly faster, about 17-18knts on smooth sea, with 4700 RPM. (but this is an 80 hp and a much lighter semi displacement boat). Isnt The orkadian a displacement hull ?

 

I only really get to test the fuel consumption when doing the longer runs, as I find lots of stop start operation burns more fuel. On a longer run, I would be better than 1 l/mile (these are naughty miles not statute). Unless you have a fuel flowmeter, its a bit hard to judge.

 

Regards

 

Paul