Engine mounts for Universal M35a

[Peter Lewis]

We plan to replace the original engine mounts on our 1992 C34 over the winter to reduce engine noise and vibration.  Our boat is equipped with the Universal M35A engine, and a PSS dripless stuffing box.  According previous posts, the M35A specifications indicate that the Vetus K100 engine mounts are recommended.  1) Does anybody have experience with this engine/engine mount combination?  2) Is there any concern that with the softer engine mounts, the PSS stuffing box will allow the shaft to rattle against the shaft log at rougher RPM ranges?