Fuel Consumption

[boatmike]

What would you experienced guys expect in fuel consumption from a semi-displacement Aquastar 33 with twin Volvo 138HP diesels doing about 10 knots?

 

[Bandit]

Not a lot to go on Assuming 10 knots is normal cruising speed say 300rpm off max then 5 to 7 gallons per hour. ie 20 to 30 litres per hour for the two engines.

 

[boatmike]

Not a lot to go on Assuming 10 knots is normal cruising speed say 300rpm off max then 5 to 7 gallons per hour. ie 20 to 30 litres per hour for the two engines.

Yes Bandit, thats more like what I calculated. Owner claims top speed about 14 knots so 10 seems reasonable cruising speed.He claims 4 gals per hour and I don't believe him!

What would you say was lowest consumption going through french canals at 4 knots max? I thought at least 2 gals per hour........

 

[benjenbav]

Max displacement speed is approx 7 knots. It might well be that the 138hp volvos are a good deal lighter than the 200hp Cummins units which I have in my Aquastar 33 and that the one you are looking at pops up onto the plane at 10 knots. Otherwise, at that speed you will be pushing a lot of water out of the way.

I tend to cruise at 10-12 knots. At that sort of speed I would expect to burn a gallon every 1.2nm or thereabouts. So, for me it's rather closer to 8-10 gallons per hour.

Great boat. A wet ride and rolls like a pig but will see you home in just about anything.

Here's a picture of us after we'd dragged the lifeboat home:

Not really.

 

[boatmike]

Thanks for that! Sounds about what I would expect. The Folorum strikes again! I just knew someone out there would know the truth. At 400HP total you will have a great sea boat under you and the Cummins are a good fit for it too I guess. My problem is that I want to potter the French Canals AND go to sea... Not an easy compromise so looking at smaller engines.....

 

[Nautibusiness]

Thanks for that! Sounds about what I would expect. The Folorum strikes again! I just knew someone out there would know the truth. At 400HP total you will have a great sea boat under you and the Cummins are a good fit for it too I guess. My problem is that I want to potter the French Canals AND go to sea... Not an easy compromise so looking at smaller engines.....

At tickover there won't be a huge amount in it between big(ger) engines and tiddlers.
They don't burn masses at tickover.

 

[Solitaire]

Here's a picture of us after we'd dragged the lifeboat home:

Not really.

That brings back memories!!

 

[benjenbav]

Photographer par excellence, of course.

 

[Firefly625]

Ben... if every you want to swap..

 

[benjenbav]

I'd be happy to swap the bloke on deck in that picture.

 

[Bandit]

Long story, following a flood at home from a plastic toilet fitting I found a copy of the report by MBY or MBM of an Aquastar 33 aft cabin with 2x 158hp VP 40b engines "Spirit of Argyl".

The estimated fuel consumption at 10 knots is about 1.3 mpg.