diesel outboards....!?

Nothing new...seen a few of these Yanmars on fishing boats in Portugal ( when they actually used to go fishing).
 
i seem to recall there was a litter collecting boat at port solent many years ago that had a Ruggerini diesel outboard. used to wake everyone up when it scooted around the marina collecting bottles that had been thrown from the broardwalk!
 
They used to have a diesel outboard on the 'harbour masters' taxi boat in Benbridge. IT WAS VERY NOISY. sorry for shouting but with that thing running you had to....
 
The old water taxi RIB in Bray Harbour, Alderney had a big old diesel outboard on it. It sounded like a hundred nails rattling around in a biscuit tin but it certainly did the job!
 
Not really sure where these might fit in. Small petrol outboards are economical, light and relatively inexpensive. A small diesel might be more economical, but would not be light or inexpensive. A big outboard is generally used for performance, and power to weight is a requirement. Not sure a diesel fits these parameters.
 
Many years ago there was an italian company called Garniti they made diesel outboards but the lower end hp was air cooled so it was horrendously noisey, we heard one running in a tank at an indoor boatshow, needless to say there were not many spectators!
 
As a crossover on the way to diesel, without the weight, cost and noise:

Depending on where you live in the world, you may or may not know about kerosene outboard motors. Kerosene outboard motors are popular in the third world because in some places kerosene costs less than half the price of gasoline. For example, in India and Sri Lanka where the fuel is subsidized (because it is used for cooking and lighting), kerosene costs a mere 1/3 the price of gasoline. So naturally it follows, operating costs are significantly lower with a kerosene outboard motor.

About 16 years ago Yamaha Marine developed its kerosene outboard motors because of the demand within the Sri Lankan market where fishing villages such as Negombo have come to rely upon them. They start on gas, then transition to kerosene underway. Know that kerosene outboards are better suited for trolling or long hauls rather than for short trips. Kerosene burns at a higher temperature than gasoline and combustion is not as efficient. Exhaust smoke is copious.

Yamaha kerosene outboards are founded upon the Yamaha Enduro, a carbureted two-stroke outboard motor series developed for commercial use (long hours of continuous operation) on small fishing boats and passenger vessels. Yamaha Enduro outboards boast enhanced strength and durability in the roller bearings, crankshaft and cylinder block, as well as an improved (chrome-plated) water pump.
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rafiki_ said:
Not really sure where these might fit in. Small petrol outboards are economical, light and relatively inexpensive. A small diesel might be more economical, but would not be light or inexpensive. A big outboard is generally used for performance, and power to weight is a requirement. Not sure a diesel fits these parameters.
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agree with all that... still like the idea of one!
 
Good enough for the EA

I used to service a few outboards in Putney for a rowing club

Most times that I was there I saw the EA cat that was powered by two Yanmar diesel outboards.Certainly could hear it coming from miles away
 
Not true. Diesels are more noisy, even in cars. Or, rather cars' outside.

Noise insulation in cars works great, not so in an outboard. Compare to a tractor where the engine is not built in.

Different diesels generations vary (indirect, direct and commonrail) but none as low in noies emission as a petrol engine of equal generation
 
In the years since Yanmar introduced the diesel outboard engine it has created waves of excitement in the marine world.

Now, instead of the fickle performance common to so many petrol outboards, the diesel outboard presents a level of stability, savings and long-term strength that make pure sense to the commercial operator.
 
WouldbeSailor said:
Ok, excuse my ignorance but why is an outboard diesel more noisy? Diesel cars aren't.
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Modern diesel cars are pretty good for noise, but there is an awful lot of engineering into combustion rates and timing, engine block stiffness, transmission beaming, then acoustics and encapsulation. Even so, you can still hear most diesel cars cackle at idle, where a gasoline engine needs a quick check of the tacho to see if it is running. Is anyone going to do this for an outboard?
 
rafiki_ said:
engine needs a quick check of the tacho to see if it is running. Is anyone going to do this for an outboard?
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Yes! Sometimes with my Yamaha 200 4 stroke (v6), on tickover and say its windy.... I have been known to think the engine has cut out!
 
rafiki_ said:
Is anyone going to do this for an outboard?
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Moderne engines are good. Suzuki 4-strokes are famous for sweet running. No noise, no vibrations. And no smoke.
With my Suzuki DF140 I had to check the tell tale to know it was running, if there was any other motor on nearby.

I do not know any diesel that matches this level, please tell if you do.
Here's first start after winter, with close up microphone (note ambient sounds)


Edit: And another
 
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Don't think diesel in a outboard will be a option. Remember without a turbocharger and intercooler the power output from a modern diesel is more or less the same as 30 year's ago. The best NA diesel was the mercedes 220D 4valve prechamber engine having 95hp at 5000rpm from a 2.2 volume.
Mabye LS knows about any better?

Easiest way to increase this engine output is mounting a compressor on. Boosting 0.4bar? This would have given aprox 110-120hp. Engine weight about 160kg? Just a thought.(Have been playing with this thought replacing 3 litre mercruiser petrols)

Having an expensive turbo and intercooled diesel (If you manange to pack and isolate it)in a outboard with a 10years expekted lifetime due to corotion resistant on a seawater cooled engine block. A heat exchanger might be necessary. The price to high in the end.
 
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