Beta 35 Owners

[Slowboat35]

I've just had a Beta 35 fitted in place of a Yanmar 3GM30. The Beta seems both rougher/harsher and noisier than the Yanmar which is a surprise, and also has quite a buzzy vibtarion at times. Does this fit with the normal characterinstics of the engine or is there - as I suspect - another cause?

 

[earlybird]

There's no way that a 4 cyl. Beta should be rougher than a 3 cyl. Yanmar. Have a look for something loose or touching when the engine moves either sideways or fore/aft.
Other suspects are the mounts. Has one of the nuts underneath an engine bracket backed off a turn or so? One problem that Beta installation notes warn against is that of of screwing the central stud too far down until it hits the bearer. Is that a possibility? Or maybe poor shaft alignment.