I have had a drivetrain vibration since I launched this spring. Over the winter, I replaced or added the following.
New Cutlass Bearing
Shaft trued up
(fixed 2 blade) pitch re-tune (to spec)
New R&D split half shaft coupling (keyed to shaft)
New R&D drive saver coupling
New PSS seal
Syptoms I've noticed:
Noticable driveline vibration in gear at varying RPM. It seems to smooth out at 1200 and 22-2400 RPM. Anything above 2400 sounds and feels like the boat is going to shake itself apart.
Under sail, with the propeller
freewheeling in neutral, I can hear a clunk with each shaft rotation. Locked in reverse, this goes away.
I've spent a few hundred bucks to have the local yard check the alignment and declare it within tolerance. My understanding is they unbolted and removed the drivesaver, pushing the the half couplings together and measured the alignment. I'm concerned about the precision and attn to detail with the yard (they don't like working on my boat 'because it's tight and hard to work down there')
I don't know where to go next. I would like to try to narrow the area of concern to prevent spending too much investigative $$$, either with my normal yard or another in the area. The regular yard wants to do motor mounts next...which I am not sure is the problem. I did not have the symptoms when I hauled out last year.
Thanks in advance.