Upper Shift Shaft Seal help, New Loose Twin Seal Style

[PeterB26]

Alpha 1 Gen 2 circa 2005

I have a leak in my shift cable and upon pulling the upper shift shaft it is clear why: There is a deep score on that shaft right where it goes through the seals. So I ordered new seal kit and a new shift shaft. My problem is I can't seem to find clear instructions as to how to install the seals and their bushings.

As far as I can tell there have been three types of seal setups over the years:

1) The really old style with a single seal; now generally upgraded (retrofitted) to the second style
2) A "new" seal assembly with the seals already installed in a large brass bushing that extends down into the exhaust port when installed
3) An EVEN NEWER kit of two loose seals and two brass bushings.

I have the third style.

Does anyone have decent instructions how to remove/replace this style seal kit into the bell housing? Most double seals are back-to-back but I found a drawing in the Merc manual that appears as if both seals are the same way around, but can't make out which way (thinking lip down toward the exhaust, but ...?)

Another poster on another board says you press these in from below but you have to be precise about the height or you won't get proper shifting... but offers no other clarity. Is this so? How do you set the height?

Any other tricks and tips? Like work-around for the inevitable expensive special Merc tool?

Thanks,
Peter

 

[Eric 3.7LX Alpha 1]

I used a piece of either 1/4" or 5/16" threaded rod, some washers and nuts. (can't remember the size, but it has to fit inside the bushings).

With the shift shaft out, inserted the rod through the bottom bushing and the top bushing. put a small nut on the rod above the top bushing, and a nut and washer below the bottom one.

Tightened the bottom nut pulling the top nut into the top bushing and pulling it down and out of the bellhousing. Cleaned the hole the bushing was in with a battery terminal brush or a 1/2" copper fitting brush.

Pushed the bottom bushing out using the threaded rod. Both nuts inside the exhaust cavity towards the middle with a washer on top of the top nut as well so it will press against the top inside of the exhaust cavity and not go thru the hole. Tighten the top nut which pushes the bottom nut into the bottom seal and pushes it out of the drive.

The nut head that pushes the seals out has to be able to fit thru the hole also, I think I rounded off the corners of the one nut.

You will want to replace the guide arm with the roller at the tip also.. The roller tip gets worn out from the shift cable. Sometimes the allen screw strips out before it's removed. You can remove the top arm off the shift shaft by using a small sharp chisel and hammer and split it.


With this style of bushing/seal, the top one gets pressed until it bottoms out in the hole. The bottom one I made flush with the outside.

Here is a picture of Fishermarks's done.

 

[Fun Times]

Post number 11 in the following link is informative of the seal direction if needed, http://forums.iboats.com/forum/engi...ard-engines-outdrives/518439-shift-shaft-seal

 

[PeterB26]

Thanks for the help.

Eric, The threaded rod trick is a good idea. I'm sure I can make that work for me with a little tinkering.

A new guide arm and set screw are already on order. Thanks for the heads up. Don't know how you are supposed to get that set screw undone without damage. The torque required exceeds the strength of the metal the screw is made from.... so you can use heat to loosen the Loctite, but that burns up your seals.....

The photo of "Fishermarks" done has the second type of seals. The ones with the stepped brass upper bushing with pre-installed seals. That part is Merc 23-805041A2.
Mine are a little different.. I'm using Merc part no 23-806036A1 which is a kit with two brass bushings and two seals loose in the package.

BUT

Thanks to Fun Times' link to the other thread he got me straight. I was concerned because it starts off with the older pre-installed seals version like on "Fishermarks," but a little further down in the thread the loose seals version is identified as being the correct part for the Alpha 1 Gen II outdrive upper shift shaft seal with good instructions as to how it goes together.


Here is a l ink to a recent on-line manual that shows a little bit about it, but not enough. Open the PDF and go to page 37 for a diagram.

http://www.boatfix.com/merc/Servmanl/14/14b4.pdf

One last thing: if a seal runs dry (without lube) it will fail. Most Merc back-to-back seals say pack some grease between the two seals to act as lube because without that one of the seals would otherwise be running dry. Would that be a good idea here?

Many thanks to you guys here for your helpful replies.

Peter

 

[bspeth]

I think you have to heat it to break the locktite.I busted the sucker too.Then I read the manual.