[C320-list] Yanmar 3GM30F motor mounts

[John morrison]

In my opinion a grounding hard enough to distort a motor mount bolt, would also result in additional/noticable damage i.e. a big smile somewhere on the keel,  opening of the keel/hull seam,  distortion of the other engine mount bolts?
Regards
JEM
1999#574

> On Mar 25, 2019, at 11:44 AM, John Meyers <jcmeyers7 at gmail.com> wrote:
> 
> Ted,
> 
> It is possible for a mounting "bolt" to be bent by a very hard grounding
> while under way. The engine still wants to go forward while the rest of the
> boat stops.
> 
> John Meyers
> #406 Wind Chime
> Muskegon, MI
> 
> 
> 
> On Mon, Mar 25, 2019 at 9:45 AM <tharrison at innovations-plus.com> wrote:
> 
>> First thanks for prior information on the topic. I went to the boat
>> yesterday  (sitting on the hard) and replaced the two front motor mounts.
>> They are not cheap.
>> 
>> 
>> 
>> I am planning on replacing the aft mounts as soon as they arrive. It is not
>> a difficult job to replace the mounts. I placed two 2 x 3's under the
>> engine
>> for additional support as I change one mount at a time.
>> 
>> 
>> 
>> If you have all the tools it only takes about 30 minutes to replace the
>> mounts.  I used a gauge to measure the distance between the nut on the
>> mount
>> and the bottom nut on the mount.
>> 
>> 
>> 
>> I did discover a couple of interesting items and concerns. Perhaps someone
>> could help / advise if this is a concern.
>> 
>> 
>> 
>> 1.       There are two screws (about 2.5 inches) that hold / fasten the
>> mount to the boat stringers. They look like a lag bolts. The front one, on
>> the port side was actually bent.
>> 
>> What material are these bolt going into? Wood? Metal plate?
>> 
>> What could be the cause of this one bolt to be bent? Of the four bolts I
>> removed only the front port bolt was bent? Not a sever bend. But the bolt
>> is
>> not straight. To replace this bolt - what is it really - a 9/16th stainless
>> steel lag bolt?
>> 
>> 2.       The 2 bolts that attached the mount to the engine on the port side
>> were rusted. They had an 7 marked in the head. I look through the Yanmar
>> manual and I do not see how water could be getting to these bolts. Any
>> thoughts?
>> 
>> 
>> 
>> When replacing the bolts that attach the mount to the engine. Should I use
>> blue lock tight on the bolts?
>> 
>> 
>> 
>> Thanks for your help.
>> 
>> 
>> 
>> 
>> 
>> Ted  Harrison,
>> 
>> Magic Moment
>> 
>> Hull 424 , 1997
>> 
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