Does this bearing need replacing?

[BoatNoobie]

Been investigating this water in LU for a couple of weeks now. Cant figure out where, since it holds pressure. Since I have a new water pump kit, figured I'll go ahead and swap that out.

When I removed the pump base, found more milky fluids. Cleaned it up and notice all this rust. The bearing rollers look fine from this angle, but who knows. Rotates freely. No odd sounds.

This is after letting the LU drain for a couple of days too. I put in fresh fluids. Shook the LU around. Let it sit for a couple of days. Then drained again. The fluid came out green/blue. Looked as fresh as could be, unlike the previous fill and drain.

Is it as easy as it appears to replace this bearing? Remove that cross nut and the shaft pulls straight up?

*edit* Also, how do I remove that retainer nut? I don't see a tool listed for it.

[EuropeanAM]

Yes, that bearing will need to be replaced.

Special tools are required, AND THE CASE MUST BE RE-SHIMMED IF YOU ARE REPLACING THAT BEARING.

[BoatNoobie]

Yes, that bearing will need to be replaced.

Special tools are required, AND THE CASE MUST BE RE-SHIMMED IF YOU ARE REPLACING THAT BEARING.

Well, hell. I do have a retaining nut wrench and bearing coming in.

Looking over the manual. It looks like I'll have to pull the prop shaft to get to the pinion gear nut, to remove the top bearing and race?

And the shins. How do I utilize them?

But you're saying this shouldn't be done by a noob???

[EuropeanAM]

I would NOT recommend this type of gearcase repair as a "DIY" item due to the extensive special tools and service techniques required.

Read through the entire gearcase section of the Service Manual paying special attention to the Shimming requirements (pinion height, forward backlash, etc).

[BoatNoobie]

I would NOT recommend this type of gearcase repair as a "DIY" item due to the extensive special tools and service techniques required.

Read through the entire gearcase section of the Service Manual paying special attention to the Shimming requirements (pinion height, forward backlash, etc).

Hmmm,. All this backlash, and measuring with gauges and such. It does seem complicated. Wonder if I can just do a tear down and pay a shop to reassemble those areas.

[tmusky1]

I did my own last summer and had to have my local Merc dealer remove and replace the pinion bearing and the shaft bearing. It requires special tools and I didn't have the time to fabricate them.
If you're not familiar with setting up gears, don't attempt this yourself.
If you pay a shop to reassemble, you may be better off letting them tear it down as well, just make sure to tell them you want to see the old parts.

[BoatNoobie]

I did my own last summer and had to have my local Merc dealer remove and replace the pinion bearing and the shaft bearing. It requires special tools and I didn't have the time to fabricate them.
If you're not familiar with setting up gears, don't attempt this yourself.
If you pay a shop to reassemble, you may be better off letting them tear it down as well, just make sure to tell them you want to see the old parts.

Mind telling me how much for parts and labor?

When reinstalling, did you do all the backlash and measuring and stuff too?

I have zero experience in all of this. I've changed the impeller 3 years ago. I do the yearly maintenance with oil, lube, and sparks. Opening it completely up..... Well yeah.

I was going to pull the prop shaft and check to see how things are in there. If the top bearing is this rusted, who knows what's it's like on the inside. Hopefully fine since it does sit in relatively high concentration of lube.

Just pulling the prop shaft, will not require any specialty tools or technique to put back in right? Literally pull out and push back in? Instead of spending $350 for the pulling tool, I have a gear puller set, and plan on using attached bolts to hook into the back of the housing. In theory, it should work.

[BoatNoobie]

Here's my $35 make shift prop puller. No where near perfect, but it got it done. lol


To me, everything looks fine, but will replace the o-ring and seals. Also, cleaned what I could reach.

[bloodman]

Very entertaining. Thank you for pics and hoping re assembly goes as well

[tmusky1]

I think it was around $200 for parts and labor. I found all my parts individually from different sources (mostly online)
My forward prop shaft bearing(big one in the nose cone)was in desperate need of replacement. It had definitely gotten hot at one time. I used a slide hammer to remove it's bearing race and used a brass drift to install the new one. Make sure to note # of shims if reusing gears.
We rechecked the gear lash after assembly.

[BoatNoobie]

Since I planned on replacing the shifter seal too, I figure I'll go ahead and remove it. The directions says to pull up on the shift rod. I pulled on it a few times and it wasn't budging. So I first gripped the inner rubber seal with a few nose pliers and pulled that upwards. Then I was left with the white bushing seal. I just used 2 flat screwdrivers on opposite sides and forced it upwards until it loosen enough to pull upwards. Hmmm, looks like I just need to grip the shifter harder and pull harder. I was afraid of breaking something.

The inner seal looked good to me. The white bushing looks good to me too. There's an o-ring underneath and it looks good. Below that is where I spotted something unusual. I don't think it's fishing line. I believe it might be a sliver of the white bushing when it got pressed into place that shaved off. I don't see how fishing line could have gotten this deep with how tight everything was. Glad it didn't fall down the chute into the gears.









Tried to remove the rear seals on the bearing carrier to get this ready, but I couldn't get those SOB out. There's no room to knock them out form the inside like a wheel bearing. I've gripped on that metal edge with vises and tug with zero movement. Going to pick up a seal puller that looks like a mini-pick axe tomorrow and see if that will work. The hole is small.

[BoatNoobie]

Alright, so I removed the seals from the bearing carrier. The top seal was a chore to remove. It was stuck in there good. I used a seal puller instead of the Mercury pushing rod. You can see how mangled that seal is. The one underneath, came out pretty easy. Thought it would have been harder since it was deeper. I'm just waiting for a new seal installer tool to come in. I bought a "Mercruiser" tool, thinking they were the same since it was the exact part number, but when I got it, it's way too big. Could probably use the ends to hammer the seals into place like a socket, but I wouldn't get the proper depths.

Anyways, my latest concern is, the orientation of the seals going back in. Looking at the image, the seals were stacked, left to right as shown. Reading my manual, this is the wording on the orientation of the seals.

Lower seal, has lip facing down(front of motor). Top seal has lip facing up(rear of motor).

As you can see, that top seal is facing the front too. Did this get installed wrong on the motor or my manual is outdated?

[BoatNoobie]

Wait a second. I looked inside the mangled seal. I now see the "lip" of the rubber seal that's hidden by the metal flange. For some reason, I was thinking the other exposed end was the "lip", since it was all rubber on the back side.

Once I get these seals put back in, I can drop it off at a shop and button it back up! Cant wait.

[bloodman]

[BoatNoobie]

Dropped off at the local shop. Quoted 2-3 hours @ $145 per hr. Ouch.

At the moment, I've been quoted at 3 hrs, but stated it'll probably be 2. We shall see. I also bent the c-clip on the shifter rod when I was putting the bushing back in. I had the bushing flush against the top of the surface of the lower unit. When I tried to turn the shifter, it wouldn't budge as all. So I pulled it back up and found out why. ~$1 part to replace.

[BoatNoobie]

Alright, got my LU back.

A few things. 1, it took 3 hours for the tech to fix this, so that was $500. 2, I would have thought he would have cleaned up my driveshaft by using emery cloth or sand paper to get rid of the rust, so that's annoying. At least new bearing/race are new. I cleaned what I could with q-tips after picture taken. Wont the rust continue spreading in it's current situation though?

I may have figured out where water could have gotten in. That white shifter rod bushing originally sat a bit higher than where it is now. At the current position, it sits below the surface of the LU. Before it was just slightly above.

One thing I noticed. I tried to pressure test the LU after installing the water pump base. Well, the 12 PSI kept popping the base upwards. This didn't occur with the old base, which I think is odd. So I installed the complete water pump, gaskets and plate to secure the base in place. Held pressure.

Going to install the LU and hopefully test it out on the water in a month or 2. Then drain LU and see if any contamination.




Future reference, instead of buying "Mercury" bearing and race, just get Timken, since that's what they are. Probably cheaper.

[EuropeanAM]

Probably could have come out equal expense by having let a trained technician go ahead and tear-down/repair. I'm sure a number of folks enjoyed reading your "travels" through your gearcase...