Force 125 shift shaft seal

[pastorbud]

I am replacing the seals on a 1987ish Force 125 lower unit.

The shift control shaft has a rubber grommet that seals it. The old grommet was held in with a metal cap that was pressed into a socket on top of the gearcase.

The new grommet is too wide in diameter to fit in that cap. (It does fit in the socket.


Looking online, it looks like all of the aftermarket seals are like that.

(Seal, 26-817472)

How is that new seal held in? Do I glue it with marine sealant?

 

[catfishcarl99]

I just replaced both the shift and drive shaft seal in my 50hp force. the shift seal on yours looks just like mine. the new seal should be the metal cap and rubber together thats just pressed into the lower unit.

 

[catfishcarl99]

in fact your seal is exactly the same part number as mine. the old cap is trash.the new seal should be one piece. mine was grey rubber and cap. looks like all rubber but one side should be the top cap.

 

[catfishcarl99]

the protruding ring goes up beveled end goes in first. use your thumbnail you shoud be able th feel the difference between rubber and cap.

 

[SkiDad]

that is the correct part number - just use a appropriate size deep socket to push it in. I used a little rtv silicone on mine just don't get the silicone on the inside part. Don't push it in too far as it will bind up the shift rod. i had a forum thread on it at one point when I did mine, the 1st time i put it in too much.

https://forums.iboats.com/forum/eng...outboards/10153846-lower-unit-shift-rod-stiff

 

[catfishcarl99]

that's how I put mine in both seals. with deep well sockets. works like a charm.

 

[pastorbud]

You're right! I see it now. Thanks.

 

[jerryjerry05]

Make sure you clean the hole real good.
The aluminum corrodes and can cause swelling and in turn pushes the seal against the rod.
OMC's gasket sealer works great for sealing the seal.

 

[pastorbud]

Roger that. Good to know. I have a little wire brush attachment for my wannabe-Dremel. Should work perfect.

 

[pastorbud]

Got it all reassembled. Thanks!

 

[jerryjerry05]

Pressure test?
Too much pressure can blow the shift shaft seal right back out.

 

[pastorbud]

I didn’t pressure test it, but I dunk tested it! Ran it up and down the river a bit today, then drained the gear lube...no water, clear blue 90 weight.

But in other news, it’s still not running right.

I’ll do a separate thread on that.

 

[jerryjerry05]

One step at a time!!
Glad it's staying blue!!

Myself, I'm really paranoid about water in the gear housing.
I check it every time I go out.

A $1000 repair bill NOT!!

 

[pastorbud]

I don't blame you. In a really old Johnson I had years ago, I changed it after each trip. It was a lot easier to just change the lube than fix the leak! Motor was old, and it would have been really hard to take apart.