How does the rest of the world cater for this ?
I think the issue is that you asked Yanmar a question that they interpreted to mean you needed to have the mounts "officially certified" as part of your inspection
. The other way to look at it is the inspector posed a question and he obviously didn't know the answer. He looked at it and he still didn't know. I'm not sure a bunch of forum members that never saw the boat will know any more.
It is possible the mounts will handle a total rollover but that does not speak to if the mounts could be disconnected from the boat. The mounts themselves would not have to fail. The mountings could be perfectly connected to engine with no damage yet not connected to the boat. It's a huge difference even if the result would be effectively the same. It's also possible that the hull
could break up and the engine would go to the deep still attached to a piece of the hull
. That result in this narrow context is preferable but not in the overall goal of vessel integrity.
I think it would be fair to say Yanmar has no intention of providing "certification" as to the ability of their engine to be held in place by another companies method of installing the mounts. It is unfair to ask them. You got what I would expect to be the answer - they can't know if the mounts will secure the engine in a knockdown.
Just how hard do you expect to be knocked? I would venture you could easily soak the masthead without the engine coming loose. The possibilities for everything else in the boat including the crew are pretty much limitless. Going keel
up with a rogue wave
smashing on top of you might not matter if the engine is held in place since the boat might not still be there either.