More Mercury 110 questions

[david-bartlett]

I have a few more questions regarding this "65" Mercury 9.8hp that I recently acquired.

I found some water in the lower unit. The gears look salvagable, but the bearings are questionable. I got the prop shaft out, and the rear gear and bearing. I figure the pinion gear needs to come out in order to get the front gear/bearing out.

So, How do I get the rear gear/bearing out of the "carrier" without breaking something? I am sure that Carl K had some special tools to work with, but I do not, so if you have any suggestions I would love to hear it.

Thanks, David Bartlett

[20mercman]

You are correct that the pinion needs to come out. Place the drive shaft in a vice, and bend the lock tab away from the bolt and remove the bolt that attaches the pinion to the drive shaft. Then with the drive shaft held in a vice, use a wood block or dead blow hammer to drive the lower unit housing off of the drive shaft. (of course, the water pump assembly needs to be out at this time) The pinion gear will fall off of the drive shaft and into the housing. Then place a scrap piece of board, 2" x 4" etc. on your work bench, and strike the lower unit open end first onto the board being careful to try to hit is as square as possible. This shock will drive the forward gear and bearing out of the lower unit. Sometimes they can be really stuck, then heating the housing with a propane torch can be enough heat to loosen the gear assembly, but they almost always come out fairly easily. There will be shims behind the bearing, so be sure to catch them and replace them when putting in new bearings. For reinstallations, I use the prop shaft and again use a dead blow hammer to drive onto the prop shaft to guide the assembly into place. They really do move fairly easily.

Steve

[david-bartlett]

Steve,

Thanks for the good advice. Is the rear gear/bearing assembly a press fit in the "carrier" or just a slip fit? I don’t want to break any expensive, hard to find parts.

Thanks, David

[20mercman]

The reverse gear is a slight interference fit into the bearing , and the bearing then into the carrier. Usually you can tap the assembly out of the carrier with a brass drift. To remove the gear from the bearing, it helps if you have a bearing splitter, that is the correct tool to remove it, but it can be done with careful use of a chisel like a wedge. You can to this by yourself, but it is best if you have three hands….Place a chisel in a vice, then have someone hold the gear assembly with the gap between the gear assembly and the bearing resting on the chisel. Then with another chisel, carefully drive it 180 degrees from the other one. This will want to push the two parts apart. Rotate the assembly around so you are working it apart as yu go. You may have to substitute thicker wedges as the reverse gear moves out of the carrier and the gap gets large enough for the cutting edge of the chisel to hit the gear. Just use common sense and it works out. Once you get it apart, you will think, "That wasn’t that bad". This will remove the bearing from the reverse gear, and you can then remove the bearing from the carrier a punch. Again, heat on the carrier will help in pulling them apart if they are really stuck, but they usually come apart fairly easily. I forgot to mention that there can be shims again, so note them and return them when putting new bearings in. I hope this makes sense. 😳

Steve

[david-bartlett]

Steve,

Your method worked great. I got everything apart without breaking anything important. I will need a couple bearings and a seal kit, but this Merc will ride again!

[dave-bernard]

If the seal surface is bad use a speedi sleeve to repair. they are $$$ but well worth it.

[david-bartlett]

quote Dave Bernard:

If the seal surface is bad use a speedi sleeve to repair. they are $$$ but well worth it.

Dave,

Thanks for that tip. I have to finish cleaning things up first, then will know more about the condition of the shaft areas.

[david-bartlett]

OK, I have another question regarding the best way to remove the shift shaft seal from the bushing. The metal piece is stuck in the bushing. I put some penetrating oil on it and will have another go at it tomorrow.

Thanks.

http://www.marineengine.com/parts/image … 0676A1.jpg

[dave-bernard]

just drive it out from the bottom to the top.

[david-bartlett]

So, I am getting through this lower unit a piece at a time. A lot different than OMC’s, that is for sure. I can see why these things go like they do with all the extra bearings as opposed to bushings. It has to make a difference in the HP that makes it to the prop.

Anyhoo, as Frank would say, I have a question about the shift shaft in the lower unit. The upper part of the shaft that resides in the exhaust tube has quite a bit of rust/pitting, etc on it. This extends right down to about where the shaft seal rides. I don’t think it will leak, but want to prevent it if possible. I can build up the bad area with JB Weld or something, but it appears that I could just flip it end for end and put the "bad" end down, and the good end would be up. The only reason I ask before I do this is that the splines are cut a bit longer on the end that goes in the upper shift shaft coupler, than those that go to the shift dog thingy in the gearcase. The snap-ring is exactly in the center of the shaft.

Anybody ever switch one of these around?

Thanks for listening.

David

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