Mattia Battistich
Great courage and commendable effort by Yanmar. However it's incorrect to state that compared to petrol engines this engine is "lighter". In fact this unit actually weighs 55-60 kg more than an equivalent power gas engine (I took the current bestselling Yamaha F40/70 hp, so 118 kg vs 175 kg), and as much as a 100 hp one. So it would be interesting to see how this extra weight on the transom will affect the overall fuel economy. Any information on SRP?
Mzungu_Mkubwa
Excellent achievement! Glad to hear that it will make inroads in the marine industry, and I hope it also comes over to the States! (There's a large market in the recreational fishing arena that ought to snap this up!) However, I'm so disappointed to hear that it was rejected in the transportation industry, though! I hope that some in the closed-minded motorcycle or automotive industry will take note once this thing takes off in the marine. Seems ideal as a hybrid (generator) option, to me!
Bob
Will the higher torque allow for larger propellers? Will the 40hp diesel match the performance of a 60hp gas outboard? What will it cost compared to an equivalent 4 stroke gas engine? I really didn't see the point of comparing fuel economy to a 90hp two stroke gas engine.
JohnMarzich
Sounds remarkable. And can only imagine what this will do to the industry as a whole in the years to come!
BlueOak
This piece reads purely like a Press Release from Yanmar. Where is the journalism?
Beautiful 3D animation. One wonders whether the forced lubrication ports being located on the inside edges of the pistons will lead to unbalanced thermal loading? (And wear.)
The performance metrics seem to be schizophrenic, sometimes against 2-stroke and other times against 4-stroke gasoline.
New tech is wonderful, but where are the prices, even if estimated?
ljaques
I'd love to see pricing on something like this. It has myriad uses in many fields. Military gensets could be 4x smaller than they now are. The video titillated me almost as much as the Turbo Encabulator video did years ago. Do watch it: https://www.youtube.com/watch?v=rLDgQg6bq7o . I think the enthusiastic Japanese Yanmar engineers and an equally enthusiastic marketing-style translator got the best of them. LOL. P.S: Yanmar, price them low/fairly and you'll sell a billion of 'em...if they are, indeed, long-lived and trouble-free.
Martin Hone
I can see the benefit of the contra-rotating cranks, but really see where they have saved weight, unless it is because they don't need a balance shaft, but the added con-rods and complicated, heavy pistons surely add weight back in. I like the low down torque which would make this a potential aircraft engine but I can't see this thing being cheap to make....
Martin Hone
Oh, and I think the reason it didn't find favour with the motorcycle crowd is - 1. ugly 2. lacking performance ( comparible to other bike engines)
T N Args
Diesel cars are on the way out because they are struggling so much with emission requirements that they need equipment that is too expensive to equip (say the manufacturers) and too needy to maintain (say buyers who are being told that they can't just use the cars for commuting because the emissions gear will fail within weeks and cost them multi-thousands to have replaced). Hence the great home of the diesel car, Europe, is witnessing a strong decline in sales, and manufacturers are saying diesel is simply the wrong solution for the future.
EcoLogical
Didn't Yanmar get the memo ... Diesels kill people ... manufacturers and consumers investing in Diesels will be left with stranded assets.