Hello Craig and all others,
Many, many thanks for all the valuable input.
Regarding the possibility of the nuts coming loose, yesterday the Yanmar dealer told me they are creating "a washer" (via an outsourced turner). I am sure there is a language barrier + my lack of mechanical engineering knowledge.
But if I understand correctly, this will be some sort of one disc that they will insert after the four nuts have been tightened, and this will prevent the four nuts from working themselves loose.
My main concern is that if the solution were so simple and obvious, why wouldn't the factory had implemented it?
SM2K #350 (2002)