How to check/install rear motor mounts in transom plate?

nickande

Cadet
Joined
Jun 4, 2012
Messages
10
I have a 95 Mercruiser I/O 3.0LX (Engine S/N :0F299792, model:4443L100HS). I recently ruined a coupler after installing my rebuilt motor with the mounting washers incorrectly (double wound and fiber washer were incorrectly placed on top). After reinstalling new coupler and attempting to realign the engine (with the mounting hardware properly installed), I still ended up having to place an extra flat washer between the transom rear mount and the bell housing. Specifically, in the following picture below, I moved the washer (labeled "f") to be directly on top of the double wound lock washer (labeled "i").
attachment.jpg

From reading other threads, this implies that my rear mounts have slipped or moved down inside the transom plate. However, I have not found any specifications that confirm this. Other than the fact I need to have the "extra" washer in place to get my motor properly aligned, is there some other specification I could check to verify that I do indeed need to have the rear motor mounts replaced (or at least moved back up)?

This link provided some tips on how to remove/install the mounts. I was hoping someone could provide the specs for the tool that was pictured in this link: http://forums.iboats.com/showthread.php?t=564217&p=3873653#post3873653

What I still don't understand is how the mounts are kept in place... (or removed for that matter). What keeps the mounts from slipping/moving back down? Seems like a poor design. Should a strong or medium "Lock Tight" be used during installation? Seems like it would make much more sense to have a "stop" or something at the bottom of the transom plate and install the mounts from the top (such that the mounts would only go so far and stop). Furthermore, how do you get the mounts out the bottom with the lock nut holder underneath the mount? So I am confused how mount are removed and reinstalled.

Additional question, how far should the mount (inner ring) be from the top of the transom plate after installation? (this is the same question as the very first question about specs. but worded differently). Should the inner ring be below, flush or above the plate? If above or below the plate, how far above/below?

What is the likelihood of the mounts moving further? That is, can I just leave this as is (as long as the engine is properly aligned)? Or are the mounts likely to further drop as time goes on and eventually cause another coupler failure?

Thanks for any help.
 

Bt Doctur

Supreme Mariner
Joined
Aug 29, 2004
Messages
19,092
Re: How to check/install rear motor mounts in transom plate?

your question tells me you might be just a bit out of your league.the rear mounts are a leading cause of coupler failure. They are pressed in place untill seated. installed correctly the mount itself cannot move. what moves in the inner sleeve.It breaks away from the rubber bonding and causes the rear of the motor to drop down.
Always to install new if over 5 years, the motor is out, and there was a coupler failure.
Ever break a motor mount in your car and have the engine torque over out of the rubber mount, same here but in reverse. The motor drops.
will try to find a pic.
for starters post #2 http://forums.iboats.com/showthread.php?t=554934
00000001.jpg
 

nickande

Cadet
Joined
Jun 4, 2012
Messages
10
Re: How to check/install rear motor mounts in transom plate?

The picture is worth a thousand words!!!! This make much more sense... I was under the impression the mounts would be installed in the transom plate instead of the flywheel housing. This also clears up why the mounts would come out the bottom instead of the top. Once seated the mounts won't move (unless rubber is giving way, thus dropping the rear of the engine).
This helps a lot!

It looks like you made the tool to be used for installation (in this link:http://forums.iboats.com/showthread.php?t=564217&p=3873653#post3873653)... do you happen to have some specs on how to make it? I guess the hardwood, socket and c-clamp might work as well.

Thanks much for the info!!
 

Bt Doctur

Supreme Mariner
Joined
Aug 29, 2004
Messages
19,092
Re: How to check/install rear motor mounts in transom plate?

I made this to install them
IMG_1385.jpg
but a correct sized socket and C clamp would also work. burn the old core and rubber out, remove the thin outer ring, remove spacer.look to see how old spacer is installed.
 
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