Engine mounts for early M35 - 30hp

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rstonge
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Posts: 64
Engine mounts for early M35 - 30hp

It looks like my forward starboard engine mount gave up the ghost this weekend.  Very heavy thumping/vibration at low speed when in gear.  Attached is a picture.  My bolts into the stringers are 5" apart and the bolt to the engine are 5/8" diameter.  I have attached a picture.

I am going to replace all four.  What are my options for getting new mounts?

From other forum posts, I see people like the Vetus K75, but I think the mounting holes are 4" apart.

Has anyone used the DF-100: ​https://www.go2marine.com/product/401809F/df-100-series-dual-flex-marine-and-industrial-engine-mount.html

Looks sturdy and at a good price.

Ron St. Onge
1995 Catalina 36MKII
Hull 1384
 

Ron St. Onge

1995 Catalina 36 MKII Hull 1384

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Siler Starum
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Posts: 113

I just ordered a full set of engine-mounts through Catalina-Direct two years ago, no worries about the dimensions and no worries if you have the correct Shore-hardness of the rubber. All worked out well to my full satisfaction.
(and I am too lazy to do experiments...;-)) )

Durk Nijdam
S/V "SILER"
Catalina 36MKII - 2001 / hullnr. 2013
Stavoren - Holland

rstonge
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Posts: 64

I did some more investigating and found a Metalastik 17/1600 stamped on the rubber of the mount (see picture).  There is a “55” stamped on top.  I called Mission Online Supply at 817-453-1900 and they think this is a Metalastik Cushyfloat 17/1600-55.  I was wrong about the length between the bolt holes.  There is an extra piece of metal below the mount with an additional bolt.  The distance is 100mm or about 4 inches.

Mission online supply sells the mounts for $31.62: http://www.missionsupplyonline.com/Parts/metalastik-cushyfloat

The height adjustors are sold separately.  I think I need an HA 12/16 from this page: http://www.missionsupplyonline.com/pdf/HA.pdf

Mission said the HA 12/16 has been discontinued since the bolts were subject to breaking, but they carry the HAD 12/16 with the larger lower nut for $64.  They said if the bolt is not broken it can be reused with the new mount.  Since the engine has run fine for 25 years with the original bolts I am going to try and reuse them.

If anyone thinks I am missing anything, please let me know.

Ron St. Onge

1995 Catalina 36 MKII Hull 1384

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Tomspo1
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Joined: 10/5/19
Posts: 6

Hi Ron. I have the same mounts and removed one today to take home and replace. I found the same website you found and am ordering them as well. I could not locate the 55 on the one I removed so thanks for sharing that. My plan it to replace one at a time. The forward mounts are easy as the mount can be removed from the engine. For the aft mounts I may jack the motor up slightly. Not sure yet.?

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rstonge
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I am going to take a crack at replacing them end of October, just before haul.  The supplier recommends thread locker.  Hopefully, they used blue as red requires heat to release.  My plan is to disconnect exhaust and prop shaft, and then use pulley to tip engine and replace one at a time.  I will have yard do final alignment in the spring.

Ron St. Onge

1995 Catalina 36 MKII Hull 1384

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Tomspo1
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I am thinking similar to do one at a time but may just raise engine up as much as possible using the existing mounts so when I take one off I am hoping to just be able to pull it out instead of lifting motor. I may have yard do alignment as well. I have done alignments in the past and it is never quite perfect even using spark plug gap tool. I have a dripless shaft seal and if it's not aligned perfectly that will leak a bit. I am going to wait till spring at this point as my boat is shrink wrapped. Please share your outcome and any tips once complete if you can. Thanks. 

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KevinLenard
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Posts: 209

If you can get the two bolts out that attach each bracket to the engine block, you really don't need to lift the engine. Just do one at a time and make the height adjustment on the threaded posts as close to the original as possible. Then follow the instructions to level them to get a spark plug feeler to slide evenly 360 degrees around between the transmission flange and the engine flange. They recommend a ridiculously thin feeler gauge thickness, but in principle it doesn't really matter what thickness is used -- it just matters that it slides evenly around with no tight or loose spots, indicating that the two flanges are exactly aligned. It takes a bit of fiddling with the four lower height adjusting nuts, but it is not that difficult if you can visualize in 3 dimensions.

Kevin Lenard
"Firefly"
'91 C-36 Mk. "1.5" Tall Rig, Fin Keel, Hull #1120, Universal M-35 original (not "A" or "B")
CBYC, Scarborough, Lake Ontario, Canada

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Tomspo1
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The only problem with that is only the forward mounts have removable arms that unbolt from the engine block. The aft mounts are the more difficult ones to remove. 

rstonge
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Joined: 11/2/08
Posts: 64

I finally had time this weekend to start the engine mount project.  The good news is the height adjusters can be reused (see picture), and the mounts are an exact replacement for the OEM mounts on my M35.
 
A 1” wrench is needed to remove the lock nuts.  There was a little play so maybe it is a metric bolt (25mm?), but 1” worked fine.
 
I am planning to do the front two this weekend, and the back two next weekend.  The back will require lifting the engine, so I will post some pictures.
 
Does anyone have thoughts on using red vs. blue thread locker on the height adjusters when attaching to the new mount?
 
Ron St. Onge
1995 C36MKII Hull 1384

Ron St. Onge

1995 Catalina 36 MKII Hull 1384

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LeslieTroyer
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Posts: 533

You may want to look at my article in the MainSheet on this very subject 
https://www.catalina36.org/sites/default/files/mainsheet/MAINSHEET_SPRING_2020_UNLOCKED.pdf

 

Les & Trish Troyer
Mahalo 
Everett, WA
1983 C-36 Hull #0094
C-36 MK 1 Technical Editor. 

Commodore

 

rstonge
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Posts: 64

Leslie,

Great article.  I am going to try the deflated basketball method.  I hadn't thought of something like that.  Thanks for the tip!

BTW: I also disconnected the exhaust in addition to the prop shaft.

Ron St. Onge
1995 C36 MKII Hull 1384

Ron St. Onge

1995 Catalina 36 MKII Hull 1384

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