[C320-list] Severe vibration at 1000 RPMs after engine mount replacement

[Art Harden]

If can reach it with dish soap, it makes  good lubricant and the just washes away. 

Art Harden
Catalina 320 “Tortuga” #243
937-477-5544

> On Dec 11, 2020, at 12:56 PM, Paul Borghese <packetpaul at gmail.com> wrote:
> 
> Do you have the idle set to 1100?
> 
>> On Fri, Dec 11, 2020 at 11:34 AM Age Of Aquariums <dan at ageofaquariums.biz>
>> wrote:
>> 
>> my perkins does the same thing , i don’t go below 1100
>> 
>>>> On Dec 11, 2020, at 8:17 AM, Paul Borghese <packetpaul at gmail.com> wrote:
>>> 
>>> A boatyard replaced the engine mounts in my Cat 320 Perkins M30 engine.
>> The
>>> engine is noticeably smoother at all RPMs except one, 1000 RPMs.  At
>>> exactly 1000 RPMs the harmonic vibration causes the engine to shake
>>> violently.
>>> 
>>> The vibration occurs every time on every transmission setting ( neutral,
>>> forward, reverse).
>>> 
>>> Any ideas as to the issue?  I have an uneducated theory. The yard used
>>> off-brand engine mounts that were not tuned to the engine causing the
>>> severe vibration.  Or maybe the bolts are not torqued to the correct
>>> specification.
>>> 
>>> Thoughts?
>>> 
>>> 
>>> Paul
>> 
>>