Yanmar 4jh4AE Fuel Consumption

[amiklic1]

Hello,

I installed Floscan 7500 series diesel unit (2 sensors) in my 7,45m displacement hull boat (Croatian-made Gull 745: "Galeb i ja" - Proizvodnja i prodaja brodica Gull 745 i Novi Galeb 6,75. Tradicionalni jadranski dizajn), but I can't find exacr consumption values to calibrate it.

Inside the boat it's brand new Yanmar 4jH4AE, direct drive.

I need idle (which is set to 850 rpm) and some running (2000 or 2500 rpm) consumption values to be able to calibrate it.

Can anyone help? I've looked here and therer, and even Google isn't my friend in this one :-(...

[Gabrielle37]

did you get information that you were looking for? I have a 4jh4ae also and am curious.
Thanks
Jeff

[CAELESTIS]

It is on the Yanmar website.

http://www.yanmarmarine.com/theme/ya...df/4JH4-TE.pdf

[amiklic1]

Thanks, but that's not the same engine. Mine has 54 HP.

During the last year or so, I found out that my overall consumption is 0,59 liters/mile.

I was on a trip of 170 miles, started with full fuel tank (200 litres) and after 170 nautical miles topped up with 102 litres.

I'm more than satisfied...

[CAELESTIS]

Try this: link.http://www.yanmarmarine.com/theme/ya.../pdf/4JH5E.pdf

[Dockhead]

Originally Posted by amiklic1

Thanks, but that's not the same engine. Mine has 54 HP.

During the last year or so, I found out that my overall consumption is 0,59 liters/mile.

I was on a trip of 170 miles, started with full fuel tank (200 litres) and after 170 nautical miles topped up with 102 litres.

I'm more than satisfied...

That actually seems like a bit much to me. I move 23-odd metric tons through the water at 8.5 knots at a relaxed cruising speed of 2400 to 2500 rpm, burning 6 or 7 liters per hour. Yanmar 4jh3hte and shaft drive.

[amiklic1]

No, it's not too much. I have 54 HP, shaft drive, 3,5 tonns boat, but water line is just 6,70m.

I'm motoring with 2400 rpm also.

Maybe you have longer WL? That shoud explain.

Don't foget this is not a sailboat, but a motorboat. The difference is huge.

[Dockhead]

Originally Posted by amiklic1

No, it's not too much. I have 54 HP, shaft drive, 3,5 tonns boat, but water line is just 6,70m.

I'm motoring with 2400 rpm also.

Maybe you have longer WL? That shoud explain.

Don't foget this is not a sailboat, but a motorboat. The difference is huge.

My Yanmar is 100hp.

If you're pushing hull speed, then that explains it. Yes, I have 46 feet of waterline length and 8.5 knots is well below hull speed.

[amiklic1]

Yes, I'm around hull speed.

The consumption graph is really great thing to look at. With my boat, there is a point in speed/consumption ratio where consumption doubles with just 1 knot of speed increase.

Here is the graph, but just a first version. It appears that, after a detailed calibration, my consumption is a lot lower than presented on this picture. Still have to make a new graph, though.

Funny thing is that I was even satisfied with this one ;-)...
Red line= consumption, Green line= speed,

[djmarchand]

The best way to calibrate your Flowscan is to do it at WOT. First make sure that your prop is allowing the engine to reach rated rpm. Then at that point you know that the engine is producing rated horsepower and the fuel consumption at that point is going to be pretty close to the specified 11 liters/hr. If you use any other point on Yanmar's prop curve then it is just an approximation using the 2.5 prop exponent and may not match your boat's performance.

It doesn't surprise me that fuel consumption doubles to achieve reach knot of speed. Slow down to a speed to length ratio of about 1.1 for a reasonable compromise between speed and engine loading.

[Chief Engineer]

Flow meters are fine for airplanes....I am no Luddite but I think some people tend to make boating too complicated.

I use a graduated stick and a watch.

That's the way we did it on Tugs