New Yanmar neander 50hp Diesel outboard.

Have a look at the engineering: wtf!!!

Technology : Neander Shark

>The key enabler for a dual crankshaft engine with a constrained piston movement by two con-rods with theoretically no piston side forces is provision for forgiveness towards tolerances, which can lead to off-design positions of the piston in its cylinder bore and unfavorable mechanical effects like scuffing, sticking or simply higher friction as the least bad of effethis<

Holy crap: twin cranks with twin con rods on each piston!!!!
 
Surely it doubles the friction losses as well? Seems a weird design.

If you look at the graphic in the YouTube vid it appears that the two conrods work together to ensure the piston is pushed and pulled vertically, rather than at an angle like a conventional one crank system. I guess this overcomes some of the friction but like you say, adds it elsewhere.
 
Have a look at the engineering: wtf!!!

Holy crap: twin cranks with twin con rods on each piston!!!![/FONT][/COLOR]

That looks very complicated. Looks like the pair of small end bearings some how float within another bearing attached to the bottom of the piston. There must be a reason they couldn't have a single gudgeon pin with one con rod straddling the other, sort of an inner con rod end sitting within the forks of the other.
 
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That looks very complicated. Looks like the pair of small end bearings some how float within another bearing attached to the bottom of the piston. There must be a reason they couldn't have a single gudgeon pin with one con rod straddling the other, sort of an inner con rod end sitting within the forks of the other.

Presumably Yanmar have tested it for reliability before taking on the distribution...


Maybe, maybe not.:rolleyes:
 
Looks like the pair of small end bearings some how float within another bearing attached to the bottom of the piston.
I don't see that. I think both little ends are part of the piston casting; nothing floating, and no logical reason why you would
 
Interesting......Bit of a design engineers wet dream.

Crankshaft is second heaviest component in an engine, so you design a weight sensitive outboard which uses two! Only the Germans could come up with that, hardly surprising though when one considers that they designed a lightweight diesel aero engine Junkers Jumo 205 with two crankshafts.

A piston design with side by side wrist pins dictating engine bore stroke ratio, more madness. Increasingly tighter emissions has driven thinking on optimal bore/stroke ratios, for example Tier 3/4 Cat C7 has a totally different bore/stroke ratio from Tier 2 engines.

I could go on and on, but the whole design has evolved without any apparent planning.

Many brilliant engine designers out there, however the really clever ones keep their real whiz stuff filed away in case somebody in mad management ever asks them to build one.
 
Interesting......Bit of a design engineers wet dream.

Crankshaft is second heaviest component in an engine, so you design a weight sensitive outboard which uses two! Only the Germans could come up with that, hardly surprising though when one considers that they designed a lightweight diesel aero engine Junkers Jumo 205 with two crankshafts.

A piston design with side by side wrist pins dictating engine bore stroke ratio, more madness. Increasingly tighter emissions has driven thinking on optimal bore/stroke ratios, for example Tier 3/4 Cat C7 has a totally different bore/stroke ratio from Tier 2 engines.

I could go on and on, but the whole design has evolved without any apparent planning.

Many brilliant engine designers out there, however the really clever ones keep their real whiz stuff filed away in case somebody in mad management ever asks them to build one.


I remember back in the mid 90's someone brought out a new aircraft diesel engine; they sold it as a replacement fit for the good ol' Lycoming found in every piper and Cessna .

Seem to remember it was a disaster; every engine blew up after a few hundred hours and the company went bust leaving everyone out of pocket for an engine that cost twice as much as a standard avgas unit.

I've sent an email to Yanmar requesting the price ; no response so far.

Anyone like to guess?

Standard petrol 50 hp OB now about £6k....

Diesel £12k????
 
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I don't see that. I think both little ends are part of the piston casting; nothing floating, and no logical reason why you would

Looks to me they found a reason. Although, if you look at their earlier videos of the motorbike they show as you say just two little ends cast into the piston

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There is a thread on WSF about what and how much you are legally allowed to fill with petrol at a petrol station, seems some people struggle to get enough petrol in one (or even several) go. To me a diesel outboard would make an outboard boat a practical proposition, whether it would offer anything over an inboard boat is another question.
 
I remember back in the mid 90's someone brought out a new aircraft diesel engine; they sold it as a replacement fit for the good ol' Lycoming found in every piper and Cessna .

Seem to remember it was a disaster; every engine blew up after a few hundred hours and the company went bust leaving everyone out of pocket for an engine that cost twice as much as a standard avgas unit.

I've sent an email to Yanmar requesting the price ; no response so far.

Anyone like to guess?

Standard petrol 50 hp OB now about £6k....

Diesel £12k????

Press release says that they expect demand from leisure sector to be small due to price 29,000 Euros!
 
Press release says that they expect demand from leisure sector to be small due to price 29,000 Euros!

Wtf!!!

There was a company rebuilding the old Yanmar 27hp ob's up in scotland. I rang up to get a price: £13k...ouch! The kit of parts to recondition the engine came to over £5k apparently.

The guy told me that using petrol in or around the rigs was banned because of the fire risk, so all service vessels big and small had to run on diesel .
 
So does this -230hp. I'm not sure youtube volume levels are reliable!
https://www.youtube.com/watch?v=p06_LTcK5BY

I tried finding more info on that one, manafactured by Maritime Engineering Group apparently. They may have gone bust or rebranded, difficult to find info.

I found doc below which shows fuel savings in commercial environment of €15K based on 1000 hours per year at 40% duty, or €24K at 80% duty. So if it can last 5000 hours it might pay for itself.

http://www.marx-ftp.de/Downloads/Ma...esel-Aussenborder/Image-Broschuere_ENG_HR.pdf
 
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