Fuel Curve for KAD44?

[jimg]

Does anyone have any data for fuel usage with a Volvo KAD44?
Cheers
Jim

 

[duncan]

jim - it's pretty flat as most of the good modern diesels

fuel consumption will be a product of HP used rather than revs once clear of the hump - which will be a product of the hull length, pitch and gearing...................

 

[jimg]

So in a Nimbus Nova 26 with a KAD44 (260hp) on a DP290 Duoprop leg what is it likley to be burning at 3000rpm?

 

[CaptainMike1970]

Jim

We have a SeaRay 315 with a single KAD44, last year the figures for cruising at 3000-3200rpm 18-22knots where
17litres/hour
3.75Gal/hour
£8/hour
1.85Litres/mile
2.45miles/gal
£0.87/mile

So far for 2007
18Litres/hour
3.97Gal/hour
£8.09/hour
1.56Litres/hour
2.91Gal/hour
£0.70/mile

Hope this helps

 

[jimg]

Thanks Captain Mike,
How do you know how many litres an hour you are using? What instruments/controls do you have on your boat?
I just have a single morse lever and no sort of display apart from analogue temp, pressures, etc.

Cheers
Jim

P.S. Not sure how you calculated your miles per gallon.. /forums/images/graemlins/confused.gif

 

[CaptainMike1970]

jim

Unlike those who can aford the flashy bits of kit to measure fuel flow rates etc I rely upon old fashioned maths, we are based at Port Hamble on C pontoon, the fuel berth is on B pontoon so I just refuel nearly each time I come back in (some times this is just a quick splash and dash), I was advised to do this to reduce condensation getting into the tank and it avoids having to que on a busy Saturday morning when all you really want to do is set off!

I record the litres put in the tank and divide by the number of hours recorded upon the engine hour meter and the trip on the GPS since the last refuelling.

I just keep a record of it all in a note book and then pop it into a spreadsheet when I get a chance at home.

Hope it helps, my figures are total usage so include the 6 knots up and down the river on/off the berth etc and that the bottom gets fouled as the season wears on etc but are real world figures.

Mike

 

[jimg]

Mike,
I am not sure about your arithmetic!
If you use 3.75 gallons an hour then one gallon lasts for 16 minutes ( 60/3.75 )
If you cruise at 20 knots then in 16 minutes you travel 5.3 miles ( 16/60 x 20 )
So I reckon you are achieving 5.3miles/gallon not 2.45?

Cheers
Jim

 

[CaptainMike1970]

Jim

In theory you are correct with the arithmetic, however what really knackers the maths is the time spent NOT at 20 knots, like up and down the river at 6 knots or inside Poole Harbour at 10 knots so the 3.75 gal/hour includes this low speed and low fuel consumption.

The figures posted are the average for the full year.

However for passage planning I work on slightly over the worst ever fuel consumption I have experienced on a single trip (very heavy weather into the wind and a spring tide etc) of 35 litres per hour or 2.5 litres per mile (which ever gives the worst case) and then still allow for a reserve. Better safe than sorry!!

I would love one of those real time trip computer things to get the fuel useage when actually cruising at 3200rpm and 20+knots and thus avoiding the skew the 6 knot stuff up the river has on my figures but they seem every expensive for the potential benifit they give.

Happy boating. Mike

 

[Its_Only_Money]

[ QUOTE ]
Jim

We have a SeaRay 315 with a single KAD44, last year the figures for cruising at 3000-3200rpm 18-22knots where
17litres/hour
3.75Gal/hour
£8/hour
1.85Litres/mile
2.45miles/gal
£0.87/mile

So far for 2007
18Litres/hour
3.97Gal/hour
£8.09/hour
1.56Litres/hour
2.91Gal/hour
£0.70/mile

Hope this helps

[/ QUOTE ]

Hum, how come you are burning slightly more fuel per hour than last season but your cost per mile has gone down did your fuel get cheaper /forums/images/graemlins/confused.gif

 

[CaptainMike1970]

In 2006 we got 2.45 mile/gal and SO FAR in 2007 2.91 miles/gal (typo in text) which I think is a function of where we have been plus a major factor is that the boat is more efficient earlier in the season due to less weed/slime/growth on the bottom etc where as the 2006 figures go right though to November when we had her lifted out and she had a very messy bottom by then!!!

The figures are only averages taken at each fill up and obviously are effected by where we have been and what we have been using her for but I find them interesting all the same.

Mike

 

[bartonwood]

Windy published their performance test results. This link is for the KAD300. I would imagine that the KAD44 is very similar.

http://www.windy.no/downloads/28_GHIBLI_%20KAD300DP_Ggearratio_1_68_1.pdf

 

[jimg]

Cheers, I am glad somebody looks at old threads! /forums/images/graemlins/cool.gif