Fuel Consumption 75hp engine..

[boatman61]

Hi, looking for info from Jeaneau 43 owners or those with similar sized boats with 75hp engines about average fuel consumption and range..
I am delivering a Jeaneau 43DS which has no other form of charging other than the engine which means I will have to run the engine maybe 3 times a day to keep all the systems functioning like domestic, nav lights, AP, VHF and instruments..
The fuel tank is 201 litres and the journey is 1500nm approximately.
To those who have boats with 75hp engines, what rpm do you run at for best fuel economy and what kind of consumption can I possibly expect.
Possible refuelling stops are Balearics, Sardinia, Sicily.. however I am looking to minimise stops to avoid falling foul of Covid regs.. Italy for example can require a PCR on arrival and if positive means a quarantine which delays the delivery..
The final destination is Greece but that's not a big worry as if a test is required and is positive we can quarantine on the boat.. I hope, or the owners bill gets bigger.

[jibstay]

Our Yanmar consumes about a gallon per hour at 2400 rpm. 3/4 throttle is approximately 2800.

Since replacing our fixed-blade prop with a Flex-o-fold, we get between 6 and 7 knots at 2400 rpm.

[jibstay]

I forgot to mention, that’s a Beneteau 473.

[boatman61]

Thanks Jibstay.. hopefully I'll be sailing when charging so at 53 galls US that'll give me 26 charging periods at 2hrs/charge or 7 days sailing if I don't hit calms and have to just motor..
Think I'll ask the owner if he's prepared to invest in a couple of 25L jerry cans for back up.. that way I may make it with just the one stop at Cagliari.
Mind, March is windy in the Med so...

[laird]

I'm surprised that you asked this question BM ,I thought you were the fountain of all boating knowledge :-)

[Snore]

My generic SWAG is 1/4 GPH (1.2LPH) per 25hp at 1800 rpm. 90%of the time the estimate is high, except westerbekes. Those engine are 15%more.

[edsailing]

If you're motor sailing, 15-1800rpm will be fine and will give you a lift of about 1.5kts in boat speed while consuming about 0.4gph + my experience delivering these in the Med.

[donradcliffe]

It all depends on your patience. If you want to idle the engine out of gear at 1200 rpm just to charge, figure on 0.33 gph. If you want to motor at 6 knots, figure 1.2 gph. Five knots 1 gph.

My experience is that the turbocharged engines burn a bit more than the naturally aspirated ones until you get significant turbo boost at say 2 gph. OTOH, if it is a saildrive, they are about 15-20% more efficient than a shaft drive.

My experience in the Med is that if you want to average 6 knots, you will be motoring 50% of the time.

[boatman61]

Originally Posted by laird

I'm surprised that you asked this question BM ,I thought you were the fountain of all boating knowledge :-)

Never claimed to be.. if I think I can help I will chip in my 0.5 cents but never claimed to be a font..
Normally boats like this have bells and whistles, this has no charging alternatives and its a dodgy time of year with gales sweeping down from the Golfe de Lyons both sides of the Ballearic's and both ways between Sicily and Greece so getting as much info as I can makes sense.. getting caught out because of an ego is silly.
Anyway.. most things I know is hand me down knowledge so I try to pass it on whenever I can.

[boatman61]

Originally Posted by donradcliffe

It all depends on your patience. If you want to idle the engine out of gear at 1200 rpm just to charge, figure on 0.33 gph. If you want to motor at 6 knots, figure 1.2 gph. Five knots 1 gph.

My experience is that the turbocharged engines burn a bit more than the naturally aspirated ones until you get significant turbo boost at say 2 gph. OTOH, if it is a saildrive, they are about 15-20% more efficient than a shaft drive.

My experience in the Med is that if you want to average 6 knots, you will be motoring 50% of the time.

Hmmm.. I'm happy with 5kts, most boats I've been on 2300rmp has been the sweet spot though on my last boat with a John Deere she seemed happiest around 1800rpm which gave me just under 6kts..
Anyway 1/3rd gall/hr ticking over will be nice if that's the case.

[sail sfbay]

Originally Posted by boatman61

..........To those who have boats with 75hp engines, what rpm do you run at for best fuel economy and what kind of consumption can I possibly expect.........

I cruise my Hunter 46 with 75 hp Yanmar at 2500 rpm. Fuel consumption is maybe 1g/h, albeit never measure it. This thread might be helpful in estimating fuel consumption.

https://jeanneau.proboards.com/threa...#ixzz5i5pA8WDv

[Chalifour]

We have a DS 43 with à Yanmar 75 hp. We cruise at 2500 rpm and and charge our batteries occasionally at 1200 rpm for 60 to 90 min. We consume between 3 and 3.5 litres/hr. We have a 200 liter tank,
Cheers!

[raycullum]

I run a 77hp Yanmar Turbo diesel 4jh3 TE in a 31,000 sailboat. At 2000 rpm's it burns 1 gph. At 2500 rpm's it burns 1 1/4 gph.

[mitgroup]

Originally Posted by boatman61

Hi, looking for info from Jeaneau 43 owners or those with similar sized boats with 75hp engines about average fuel consumption and range..
I am delivering a Jeaneau 43DS which has no other form of charging other than the engine which means I will have to run the engine maybe 3 times a day to keep all the systems functioning like domestic, nav lights, AP, VHF and instruments..
The fuel tank is 201 litres and the journey is 1500nm approximately.
To those who have boats with 75hp engines, what rpm do you run at for best fuel economy and what kind of consumption can I possibly expect.
Possible refuelling stops are Balearics, Sardinia, Sicily.. however I am looking to minimise stops to avoid falling foul of Covid regs.. Italy for example can require a PCR on arrival and if positive means a quarantine which delays the delivery..
The final destination is Greece but that's not a big worry as if a test is required and is positive we can quarantine on the boat.. I hope, or the owners bill gets bigger.

Our Yanmar 4JH TDE 77hp engine delivers 7 knots in still water at 2400RPM. In those conditions we measure fuel consumption at 1.1 to 1.2 GPM. Our boat is 30,500 lbs monohull.

[boatman61]

Thanks guys.. good info giving me some idea of what is possible, methinks a couple of 25L cans of fuel extra is a definite for peace of mind..
Much appreciated..