Final drive seal

[alexis291]

Greetings,
I was wondering about other people's experience of replacing the seal in the final drive.
The one in my K1100 RS was leaking slightly so I replaced it with a new seal. This turned out to be a much easier job than I thought. I was surprised though at how easily the new seal fitted into the housing and in hindsight I should have put a bit of sealant around it when I fitted it. Has anyone else had problems with this seal leaking due to being a poor fit?

[alexis291]

I should add, to be clear, that the new seal is leaking. Just the odd drip.


K1100RS 1995

[billday]

There are threads on this topic, have you looked for them?

[alexis291]

Yes but nobody has mentioned new seals leaking!


K1100RS 1995

[jay1622]

I just did mine about two months ago. Was everything spotless clean, free of oil and debris when you coated the threaded ring with Hylomar? Did you use it? Torque specs followed? Going to look for the thread I used... It worked very well for me.

[jay1622]

Bingo! This is the thread I used...

http://www.motobrick.com/index.php/topic,7029.0.html

One other thing I noticed when I rebuilt mine was that if my seal wasn't perfectly set (depth) in the threaded ring, one of the seal lips looked to hang over the pinion shaft. Make sense?

[jay1622]

Notice the outer lip of the seal on the pinion shaft. I don't know if this will help you, but imediately after that lip, the shaft begins to taper down. Is yours just after that taper on the flat (sealable) portion of the shaft? If so, that would be an issue, but not by much. More to the point; however, any chance the inner seal hyperextended on install? So... Hylomar used? Inner and outer threaded ring threads spotless (wiped with acetone and debris blown away)? Pinion seal correct depth?

Here's a pic of mine before I installed the nut. See the taper and how close the outer lip seal is?

[jay1622]

Lastly, and more on point with your original question, in the last few months I've replaced a rear main seal, a final drive outer seal and a counterbalance seal (05 RT), my K75 pinion seal and a ton of other trans seals; all similar to the final drive input pinion seal mentioned here. I too noticed this particular seal was MUCH easier to remove and replace in the threaded ring than the others.

Hope all this stuff helps!

[alexis291]

Thanks for the replies folks. However, I don't think I've been specified enough about which seal I'm referring to. I mean the seal in the final drive unit at the rear wheel. The one that sits behind the brake disk.


K1100RS 1995

[Laitch]

However, I don't think I've been specified enough about which seal I'm referring to. I mean the seal in the final drive unit at the rear wheel.

You still need to be more specific, alexis. Jay's post have been specific. Perhaps you could use a diagram from a parts fiche and indicate the diagram number of the seal or take a photo of the specific area of the rear drive then post it here.

[jay1622]

 :mbird

 :clap:

Uhhh... Can't help ya there.

[alexis291]

The seal is no.1:

http://www.maxbmwmotorcycles.com/fiche/Diagrams/B0000748.png?v=07012015

[Quiltzig]

I just replaced the same seal on one of my K1200RS bikes.

As others have said, it slid out much easier than expected, and it was also really easy to slide the new one back in.

Did you measure the seal depth in the housing of the old one before you pulled it out? I measured mine very carefully to ensure that the new one went in to the exact same depth.

As stated by others, ensure all surfaces are spotless before putting in the new seal. I did have a bad leak with the old seal, but the new one has been fine. I did not use anything around the outer edge to seal it in place, as my manual said to just lube this edge with a little trans oil.

Hope this helps.

[alexis291]

The seal was flush with the housing so I put the new one in to the same depth. Perhaps that's wrong? The only unusual part of fitting the new seal was how easily it went in, as I have said. My plan is to remove the wheel and brake disk, clean up the leaked oil and then run the bike in gear to see where exactly the oil is leaking from. I'll put some sealant on the outside of the seal when I re-fit it, which is what I expect I'll end up doing.


K1100RS 1995

[F14CRAZY]

My BMW dealer charged $329.16 last week to replace the ring gear seal in my final drive. I took it off the bike myself and brought it to them. If you feel like giving up there's that option

[Quiltzig]

The seal was flush with the housing so I put the new one in to the same depth. Perhaps that's wrong? The only unusual part of fitting the new seal was how easily it went in, as I have said. My plan is to remove the wheel and brake disk, clean up the leaked oil and then run the bike in gear to see where exactly the oil is leaking from. I'll put some sealant on the outside of the seal when I re-fit it, which is what I expect I'll end up doing.


K1100RS 1995

My seals were flush with the face of the drive. I have 4 bikes and on all of them it is this way.