SV Snufkin

Hi there,
Sorry that this is three years too late! I didn't even notice this until now!
I hope you got your problem solved.

I did eventually, and it turns out my problem was actually caused by too large a gap between cutlass bearing and prop, causing torsional vibration. Seems so obvious in retrospect, but a whole variety of mechanics - including transmission company manufacturer staff didn't come to this conclusion. It was a combination of that and my flex mounts being too flexible, or rather flexible enough to aggravate the situation.

It was finally figured out and fixed by the team at Coecle's Harbor Marina where I stay in summers now. They manufacture boats, so they really know their stuff.