Gimbal Bearing Install issues - 1988 Merc 350 mag alpha one

[Fastrack]

Hi all,

I bought my merc tools from whoya on eBay. Seem like quality pieces. A few weeks ago I spent quite a few hours aligning the engine on a boat I just bought. Had to lower the front of the engine about 1/4". Alignment bar went in smooth as butter. Until I rotated the engine! I could barely get the bar in.

I bought a coupler and I'm going to install it this weekend. When removing the engine mount bolts, I discovered the starboard rear mount is busted (as the engine is sitting on the fiber washer and the mount is flush with the flywheel cover (port side its recessed). More parts ordered

Anyway. I oringinally purchased this Merc gimbal bearing (permalube) because of a growling sound, which I figure is very likely the messed up coupler.

Since I ordered the gimbal bearing and I'm installing a new coupler I figured I'd put the new bearing in even though the old one seems smooth.

I positioned the engine where the bar slid in like butter, and used the alignment bar with the driver drilled per spec (insert into coupler and back it out 1/4" and drill). I had a heck of a time installing the bearing probably because the coupler is off center or angled to one side or the bad rear mount. Started with a normal hammer and upped it to a 3lb one, still had a heck of a time. Too bad I don't own a dead blow hammer!

After it was installed I had to align the bearing with the coupler by pulling the alignment bar starboard, now it's smooth as butter. I know Don said not to use a tool like this, but I figured I'm replacing the coupler anyway. I can see why he says this, because of the issue I had!

Here are 4 photos bottom, starboard, port, top. You can see in the bottom one, that the cartridge looks squashed compared to the rest?

Does that mean the tolerance ring didn't crush evenly ?

Bearing is smooth and I had the correct driver so the inner race was never touched.

I'm trying to decide if I should pull it (proper tool form whoya) and replace the tolerance ring and reseat it? More damage instead of just leaving it?? Could the small amount I'm seeing in the photos cause alignment problems?

Am I worrying about nothing? I measured with a caliper and the bottom and sides are evenily pushed in (within .002") but the top seems to be .018" further out (towards the stern). Assuming the casting is even, I was measuring to the flat part as seen in the photos.

Ben

 

[Bt Doctur]

The bearing is just driven in untill fully seated, has nothing to do with a alignment bar or coupler.

 

[NHGuy]

I'd leave it as is and see how it lines up once you have the coupler replaced.
BTW, fit check the coupler against the drive splines and align bar tip before you install it on the engine. That way you will know how much resistance to expect once it's all in place.
As long as the bearing is bottomed in it's spot you should be good. Measuring against the "dumb" side of the housing doesn't mean that much unless you gorilla'd it so much that the ring was moved away from center. And it still could give you years of use, so check it as-is unless you are certain that you bent the ring thereby putting the bearing out of center. A bit of angle is ok because the bearing is designed to pivot in the ring. That's what the term gimbal is about.

 

[Fastrack]

Thanks all it makes me feel a bit better.

BT Doctur - What I used was a tool that uses the bearing driver mounted on the alignment bar inserted into the coupler to "aid" in installation. Like this, after doing this, I wish I just used the driver without the aid of trying to use the coupler.


NTGuy - Thanks for the tips. That's already in the plans - I think I have a bit of OCD! As I've read every topic on gimbal bearing install here on iboats (and other forums). The coupler I bought is a kit and replaces the yoke as my shaft does not have an o-ring seal for the coupler seal nor does the current coupler have a grease fitting, but I'll check fitment before installation!



When I say I was hard to hammer, after it was installed I could BARELY get the bar OUT of the coupler! I tried the tapping on all sides with the rubber mallet like suggested, no dice. I had to MOVE the gimbal bearing with just the alignment bar - handle towards starboard. Then it inserted like butter.

So in other words the bearing was heavily side loaded while installing, I know the driveshaft puts a heavy side load on the bearing, BUT this was while hammering.

I guess it's best to leave it and run it, as there's no sense in trashing a brand new bearing!

But Don is the MAN, I know I've read many topics that he has said NOT to use a bar like this. But I figured it sounded like a good idea, as it would help align it. Especially since I had the old bearing aligned. But I guess the "gimbal" part of the bearing masked the fact the coupler crooked to one side. Which was evident when I spun the motor

There's a bigger version of the above photo:


Ben

 

[Fastrack]

No Title

Here's a picture directly from behind with the entire bearing. Looks similar all the way around.

Ben

 

[NHGuy]

.No more hammering the align bar. Follow the process or expect fails & consequences.
If things don't work as expected come back and tell us where you are, we will get you through.

 

[Fastrack]

.No more hammering the align bar. Follow the process or expect fails & consequences.
If things don't work as expected come back and tell us where you are, we will get you through.

I'm not sure what your saying .. However when I said I was hitting the sides with a mallet, I meant as per the merc instructions to align the gimbal. I did not mean I was hammering the side to try and center the bearing it in the housing. Only to "move" the bearing in the cartridge. Which didn't work as it was too far off... So I just manually used my hands to move it slightly over and the bar slid in like butter.

I never hit anything but the end of the bar with the 3lbs hammer.

The side loading I'm speaking of was the pressure put on the bearing via alignment bar going into the coupler whilst it was not 100% in alignment.

Ben

 

[NHGuy]

I thought you had hit the bar into the old coupler. My apologies!

 

[Fastrack]

I thought you had hit the bar into the old coupler. My apologies!

Well it never bottomed out, as the driver (as pictured above) was mounted on the alignment bar - which was set a 1/4" from bottoming out! So I didn't bang the bar into the coupler.. that might damage the flywheel! I don't want to have to replace that too The alignment bar was in the coupler 100% before the process started.

I'll give this gimbal bearing a shot, it's still super smooth so it's not wrecked. I was about to pull it so I'm glad you responded!

Ben