[C320-list] replacing motor mounts

HOLLY DAVIS hdavis787 at hotmail.com
Sun Jan 22 10:26:02 PST 2012


Hi Rick,
Thanks for your reply.  It was very helpful.  It was a front motor mount and I have e mailed Westerbeke.  Since they are no longer making the 30B three engine, I a m also inquiring which mounts to use for replacement.  
I am not doing the work myself.  It is beyond my capabilities, but I have a very experienced mechanic which I trust.  I was just interested in finding out more about the process and the difficulty of the job.  And if I can get Westerbeke to comp me a couple of motor mounts, that would make me very happy!
Where are you located?I am in So Cal.Holly

> From: rsulewski at bex.net
> To: C320-List at Catalina320.com
> Date: Sat, 21 Jan 2012 15:12:32 -0500
> Subject: Re: [C320-list] replacing motor mounts
> 
> HollyHonu #264,
> 
> I replaced the front motor mounts in 1996 when I received notice of a
> Westerbeke motor mount recall the same time I was sent two upgraded front
> mounts due to a high number of front mounts that were expected to fail due
> to the rubber to steel design mount at that time.
> 
> I am thinking about replacing all four mounts given the  age of the rubber
> when I replace the cutlass bearing, as that would also be the time to
> re-align the prop shaft to the engine couple. It would then be necessary
> adjust the motor mount up/down stud nuts and / or side to side adjustment
> bolts on the motor mounts attached to the hull grind ( stringer) to ensure
> that the shaft alignment to the  engine coupler falls within tolerances to
> avoid premature cutlass bearing wear and ensure the packing gland is not
> prematurely worn allowing excessive water migration into the bilge.
> 
> Since I replaced the front mounts years ago, there are now videos posted on
> the internet clearly providing guidance and tips. I captured the process I
> used to get the job done which is similar to what is posted on the web
> videos now available on YouTube.
> 
> Motor Mount Replacement Process:
>  1.  I replaced the original front motor mounts by first separating the prop
> to engine coupler so I could later tilt the engine to slide out the mounts,
> one corner at a time.  
> 
> 2. I noted the number of stud treads exposed on either side of the up/down
> adjustment nuts and marked the new motor mount stud for that engine corner
> accordingly so I could duplicate the same adjustment setting on the new
> mount for that specific corner. 
> 
> 3. Traced the outline of the original motor mount as it rested on the hull
> engine grid ( stringer) to ensure the side to side bolts adjustment template
> spacing is recorded before removing the engine mount to hull grid by
> removing the hull attachment bolts. 
> 
> 4.  I then removed the stud adjustment nut securing the engine to the mount
> so the engine could be lifted above the mount stud in the next step. Next I
> removed the bolts attaching the mount to the hull grid so I may then be
> prepared to slide out the mount in the next step. Have the new mount ready
> to install with the nut adjustment already recorded to mirror the old mount
> tread settings noted in the preparation step # 2.
> 
> 5. Using a small pry bar,  lift the motor attachment above the mount stud,
> just high enough to slide away the old mount and immediately replace it with
> a new mount.
> 
> 6. Bolt down the motor mount to the hull grid against the traced outline of
> the  former mount, but  do not snug the bolts just yet if you are going to
> check the coupler alignment before attaching the prop shaft side of the
> coupler  to the transmission/ engine side of the coupler. Also install the
> top adjustment nut, but do not snug the adjustment nuts if you are going to
> check alignment before reattaching the coupler. 
> 
> 7. The last step was to check for prop shaft alignment since the shaft to
> engine coupler is already separated. I used a feeler gauge to check four 90
> degree couple circumference measurement points. Used the up and down
> adjustment nuts and the side to side mount bolts to draw the engine within
> the tolerance limits for each of the 90 degree points on the coupler by
> making further (small) motor mount adjustments ( up/down or side to side).
> This whole process is really a mental mind puzzle that is very logical and
> very simple once the relationship of the engine to the coupler variances are
> understood.
> 
> Lessons learned: The simply solution is to pay someone to do all of the
> work. However, I found that unless you have a yard worker who is very
> proficient at this type of work because they have had some experience and
> have the patience to get it right, you may find the quality of your work
> superior to a first time episode with an inexperienced yard worker.  Even an
> experienced yard worker who is less inclined to be accurate when rushing to
> finish the task with a high degree of accuracy may not do as well as you may
> do. 
> 
> I had to do-over the coupler alignment myself in 2001 after I had the first
> cutlass replaced when I upgraded to a stainless shaft and also needed to
> have the prop strut re-bedded because we had wrapped a line around the prop
> that resulted in the engine being stalled out while under 2,500 rpm load  as
> we were motoring along that resulted in damage to the bronze shaft and the
> strut. After checking to see if the repair/replacement job had been
> completed as expected, I found that the engine was badly out of alignment
> when I separating the coupler to check if the alignment was done correctly.
> The alignment had not fallen within the tolerances specified by Westerbeke.
> It was a weekend after the yard help had left for the day, but it only took
> me an hour to get it right since I had the earlier experience with the motor
> mount replacement in 96. I have since put 600 hours on the boat over the
> last decade and the cutlass remains firm but is beginning to show natural
> wear. However, due to the correct shaft alignment over the years, my packing
> gland wear and drip rate has also been minimal.
> 
> By chance was your failed mount a front mount?  The reason I inquire you may
> have a reason to contact the engine manufacturer. If you have a Westerbeke
> you may learn if your engine was on the list for motor mount replacement and
> even if you have another engine manufacturer it may be worth a phone call to
> check  with a technical support person who may have the authority to comp
> you  some replacement motor mounts.
> 
> Hope this message proves to be helpful.
> 
> Rick
> My-Ria Hull #277 
> 
> -----Original Message-----
> From: c320-list-bounces at lists.catalina320.com
> [mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of HOLLY DAVIS
> Sent: Friday, January 20, 2012 8:08 PM
> To: c320-list at catalina320.com
> Subject: [C320-list] replacing motor mounts
> 
> 
> Rick,I have a 1995 320 and just discovered that one of my motor mounts is
> broken and the others are rusty, so I am looking to replace all four.Have
> you changed yours and how did it go?HollyHonu #264
> 
> > From: rsulewski at bex.net
> > To: C320-List at Catalina320.com
> > Date: Sun, 6 Nov 2011 19:40:10 -0500
> > Subject: Re: [C320-list] Flexible coupler effectiveness?
> > 
> > Shawn,
> > 
> > I have a Westerbeke 30B engine and it also transmits a fair amount of 
> > vibration, depending on the selected RPM on my 95 320.
> > 
> >  I am thinking about changing out the motor mounts when I need to 
> > replace the cutlass bearing in a few years. It also occurred to me to 
> > consider changing out the rubber hose that connects the stuffing box 
> > to the thru-hull prop shaft tube given the age of the boat.
> > 
> > Have you considered that your motor mounts may be contributing to 
> > excessive vibration and engine movement that could impact the wear and 
> > tear on the cutlass bearing?
> > 
> > I wonder if any other owners of 93-97 boats have had a need to change 
> > their motor mounts or that thick rubber connecting hose between the 
> > prop shaft hull tube and the stuffing box?
> > 
> > Rick
> > My-Ria #277
> > 
> > 
> > 
> > -----Original Message-----
> > From: c320-list-bounces at lists.catalina320.com
> > [mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of Shawn 
> > Maloney
> > Sent: Sunday, November 06, 2011 11:01 AM
> > To: C320-List at Catalina320.com
> > Subject: [C320-list] Flexible coupler effectiveness?
> > 
> > I have a Perkins engine in my 93 C320.  Though these engines are tough 
> > and reliable, they are not as smooth as the Yanmar.  I have 2100 hours 
> > and plan to replace the cutlass bearing as a maintenance item.  At the 
> > same time I may consider a stainless steel shaft ( as some have done 
> > on this list) and I am considering adding a flexible coupler.  It 
> > seems that the coupler is about 1 ¼ inches thick and I would resize the
> shaft to compensate for this.
> > 
> > 
> >  
> > 
> > I would like to hear any comments as to the effectiveness of the 
> > coupler at reducing vibrations and adjusting for alignment issues.  
> > Thanks
> > 
> >  
> > 
> > Shawn Maloney
> > 
> > Hull #14
> > 
> > 
>  		 	   		  
> 
 		 	   		  


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