[C320-list] Motor mounts

[Troy Dunn]

Tim, for your hull you almost certainly have the 3GM30F Yanmar engine.
There are numerous discussions on many forums about that shudder that
happens when you rapidly throttle down to shift into reverse.   Throttling
back so quickly causes the engine drag and the shaft momentum to cause
enough shaft whip to really make quite a racket.   Assuming this doesn’t
happen when you throttle back a little less rapidly you really only have
two alternatives.   The first is to adjust the minimum idle rpms up 100-200
rpms.   This will probably be above what the manual says but it will
definitely solve the problem.   Option 2 is to try and be a little slower
on  throttle.   This sounds easy but I have never mastered it.   We all
know what it can be like trying to navigate an unfamiliar marina with a
little bit of wind and a ton of spectators…..

Unless you are having vibration issues at higher rpms I would forgo the
alignment and engine mount unless you are certain the mounts are bad.   Get
someone who really knows Yanmar mounts to take a look at that, or post some
pics in the galley or on FB.

Cheers

Troy Dunn
Hull #514