9.9/15hp Upper Mount Dimensions

[JohnnyGuy]

Hi All,

My '76 Johnson 15hp needs new upper motor mounts.

I was reading Leeroy's website and he did a DIY mount where he cut out the rubber from the mount and used another OMC bushing with a custom machined shaft.
I've also been reading some other posts where people have used different car bushings, etc...

I'd like to find a properly sized Polyurethane bushing and I was wondering if anyone would have off-hand, the ID of the metal mount after the original rubber bushing has been removed.
It would also be helpful if someone had the thickness of the mount where the bushing would get pressed through.

Trying to order parts so that I can complete the job once I start it.
If no one has the dimensions handy, I guess I'll get them when I tackle the job. :joyous:

Cheers!

 

[JohnnyGuy]

I removed the powerhead on my 1976 15hp Johnson (15R76A) today.
to swap the upper motor mounts from a 1986 Johnson 15hp (J15RCDE) parts motor that I had..
The ones on the 76 were pretty much shot. The ones on the 86 were better but not my much.
In the attached photo the ones on top were from the 76 the ones on the bottom were from the 86.

Since the thrust block (318993) that goes along with the mounts was shot as well I swapped the one from the 86 (329045) along with the "link" from the 86 (329047)(which has two bends in it to conform to the block, as opposed to the one from the 76 (319084) was just a straight plate).
I have not reinstalled the powerhead yet but it definitely doesn't have near the play that it did. I have noticed that the thrust block (mount as evinrude calls it) doesn't fit SNUG between the upper Mount and the link, though I think I remember seeing in another thread that it doesn't matter.
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I have ROUGHLY cut out the rubber from the old mounts.
I am going to clean the rest of the rubber up from the shaft and the mount body, then I'll post the dimensions on here for anyone who might want them in the future.

I noticed another post recently about 3D printing old parts which are NLA.
I have a friend who works for a manufacturer of plastic Autoparts, he has a 3d printer, so I had him 3D print me a choke knob for an old 2hp. Besides being gray it turned out pretty good.
That whole thread got me to thinking though, and after speaking with him, we are going to try and print a mould/jig, that can be used to cast a new polyurethane bushing in place of the rubber one that was removed...
If anyone has any idea on what Durometer polyurethane I should use I would appreciate the input.

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[racerone]

They are quite proud ( $$$ ) of those mounts.

 

[JohnnyGuy]

They are quite proud ( $$$ ) of those mounts.

They sure are. As of this post $138ea. CDN.

 

[racerone]

I do not believe I will ever buy new ones.-----Would buy a complete parts motor first.

 

[JohnnyGuy]

I do not believe I will ever buy new ones.-----Would buy a complete parts motor first.

Agreed.
They all tend to go bad though from my research.
I am hoping I can figure something out with creating a Polyurethane "conversion" that would be longer lasting.

 

[racerone]

Yes there was a posting somewhere ( I forget ) of someone using automotive mounts.----Did a neat adaptation with them for less than $10 I think.------I have some new ones on hand and lots of good used too.