I'll bet that diesel will be a real symphony of sound humming inside an aluminum hull
This is certainly the million dollars question.
I actually hope to hear that noise for hours and hours day after day while I am out fishing and all these other boats that require $200/day in fuel to take out fishing are sitting in driveways and marinas all over the country.
Because, lets be honest here, that's the fate of 99% of all the boats in this country.
I have thought about this issue, and this Deutz is known to be quite a shaker! I have purchased liquid filled mounts, and will be using a cv jointed shafted from a Porsche instead of U joints to try and eliminate as much vibration as I can, and the box over the engine will be insulated.
The entire floor will be filled with foam with a 2" layer on top, covered in aluminum and a rubber mat, This should help absorb sound and vibration.
This may all be a waste of time but I think it will be ok. If it is horrible I can always put in a different motor later. the great thing about this setup is it will be a piece of pie to change motors should I decide to later.
I actually have a Subaru EJ22 with a converted harness sitting right here right now. That would be a nice runner in this boat.
Maybe I'm an idiot and should've stuck with a 20-40 year old inboard/outboard setup like is most common here. TIme will tell.
Btw some of my orders are here. Gluvit, pop rivets, Jegs rivet gun, some aluminum pulleys,shark hide, clecos, etc. etc
And I made my first cut. no turning back now!