Fuel consumption SO 32

[rodgerg]

Hi folks can anyone tell me if they have ever worked out the fuel consumption per hour for the SO 32. I have just discovered one of the Mapping programmes i use ask for this info and I have not got a clue. A non working engine hours instrument does not help. Obviously I know that what speed its run at will make a difference I just need a ball park figure. Thanks Rodger

[Don Reaves]

I found a graph indicating fuel consumption as a function of RPM for my engine on the Yanmar web site. Perhaps you can find that data for your engine. Of course, you would need a tachometer to tell you the engine speed to calculate fuel use at a given speed through the water.

On average, I burn 2/3 gallon of fuel per hour in my SO35 with my Yanmar 3GM series engine. My typical speed while motoring is about 6.5 knots.

Don

[ianqv]

Hi

I've got an S/O 37 with a volvo 40hp.
I have a 3 bladed feathering prop.
Shoal keel

I burn about 3/4 gallon per hour - at approx 7knts

Ian

[flightdeck]

we have the 3 cyl volvo 19Hp and burn around 2.5L I do calculate on 3L just to be on the safe side.

Cheers

[tedp]

I keep an engine hours and fuel log on board but I won't be there for at least another week. When I go there I'll look it up for you. I think Flightdeck's estimate is on the safe side.

[Anwen (Deep Joy)]

Ted, I always used to reckon on about 1.5 litres per hour flat out for the 2GM20F in Deep Joy. I would cruise at around 6 knots under engine, and the fuel consumption was around 1.2 litres per hour, although this was just based on approximate calcs.

[Anwen (Deep Joy)]

Ignore my last post, I found the performance curves and the fuel consumption is between 3 and 3.5 litres per hour for the 2gm20. Sorry if I misled anyone.

[MartyB]

The 3-3.5 L per hour would be on par with my 2gm 16? probably a predecessor to the 2gm20. I am usually 3/4 gal so a bit under 3L at 6 knots. If I go hull speed or 6.6, I use over a gal an hour, or at or just under 4L. I also do not have a tach, so that does not help any of this I know.........I've heard of one local fellow getting .5gal er hr with a std fixed prop, and about the same as me with a max prop. So lighter wt props will use less fuel!

Marty

[electricmonk]

fuel consumption is always hard to determine what with the accuracy of the Jeanneau fuel gauge and the volume of the fuel tank being a relative unknown.

for example my 200 litre tank actually holds 247 litres. the good news is that marine diesel engine fuel consumption is very predictable, e.g. 50hp WILL cost 11 litres per hour, new engines are way down the road of the law of diminishing returns so new developments wont improve on this figure significantly.

fuel consumption varies with rpm so everyone will have a different reading. so a best guess is that 1 litre per hour is equivalent to 4.0/4.5hp

use the power curve for your engine, for a given rpm read off the expected power output and divide by 4.0 then 4.5 so you will have two numbers, these will give a good indication of where the actual fuel consumption could be at that speed assuming the engineering is correct.

[tedp]

Based on estimated engine hours and fuel loaded I have found fuel consumption of my SO32 varies between 1.57 and 1.82 litres per hour. I have a Volvo 19hp engine. The fuel consumption was monitored over three periods of 62, 21 and 27 hours and the total fuel loaded added up, starting with a full tank and making up the amount burned.

The hours estimated were taken from the log, but inevitably this is not very accurate. The engine load or RPM hasn't been taken into account, and there is some fuel consumed by the heater.

[rodgerg]

Thanks very much for digging this out for me. All I need now is find out whats gone wrong with my electrics