[C320-list] Motor mounts

[Bruce Heyman]

Hi Dave, 
My experience has always been that when you have specific rpm's that results in resonance it is either due to shaft whip or misalignment of the shaft.  In the past when I've had that problem it would go away when I aligned the shaft.  Also, my experience is that when a motor mount fails you have very serious shaft misalignment and when you look at the motor mount you will see the rubber is detached from the metal.
Bruce
Bruce Heyman
Somerset #671   San Pedro (LA) California

-----Original Message-----
From: C320-list <c320-list-bounces at lists.catalina320.com> On Behalf Of Dave Hupe via C320-list
Sent: Sunday, November 5, 2023 6:48 AM
To: C320-List at Catalina320.com
Cc: Dave Hupe <hoopdtwo at yahoo.com>
Subject: Re: [C320-list] Motor mounts

I have the Perkins M30 engine in my 1994 #32.  I have vibration that I don't like at certain rpms and the engine does not like idling too low. I have examined my motor mounts and manually jiggled theengine as hard as I can, but don't  see/detect anything that says I should replace my mounts. I have learned to throttle up/down to get a smooth motor cruise for different speeds desired and an easily get 6 knots without pushing the engine hard. I don't like the idle speed my motor wants when it comes to shifting between gears without the motor shuttering. Shifting sounds harder than i like but it works.
NOTE everyone .... I suggest mention your specific engines when doing posts like this.  Specifics helps each of us know the applicability of your information to our own situations.
Dave Hupe
1994 C320 #32
Holland, MI