Rear drive end: Oil find its way to the brake area

[Micha]

I opened the rear brake as I was not satisfied with its performance, and found that the rear drive area is not oil tight.
I had that area overhauled completely and put about 100 km on the clock since.
Of course that the big rubber seal for the driving dog final drive was also replaced (p/n 26113004370).
In fact, it still looks like new, after cleaning it. I could not find any damage on it.
I would love to hear ideas on where to look for that leak, as I intend to sent a purchasing list to Salis.
Thank you and a nice week.

[vechorik1373]

You need to take the final drive apart the rest of the way, and when you get the ring gear out, LOOK at the surface that the seal runs on. If it is grooved, where the seal lip runs, another new seal, will not fix it. There must be a smooth, unworn surface or oil will creep under the lip and it will leak. CR makes metric speedi-sleeves for the repair of worn shafts, that can be driven on over the surface, to fix a worn shaft surface. You must either do this, or have the surface welded up, and turned down and polished, or the leak will continue.

[Micha]

Thank you Vech.
By "ring gear" - do you mean #8 at Sali's drawing? -

[vechorik1373]

No, that is the cover for the seal.

The splined shaft itself, that the ring gear bolts onto, (which is available new, but it is not cheap) is 33 12 0 026 232
A new shaft will solve the problem.

[Micha]

Thank you.

[Micha]

After further thought, could it be that this is because the filler cap that PO put there, is completely sealed?
As far as I understand, there is a need for a plug that also serves as a breather.

If so - where are these available?

[Micha]

A few more thoughts of the rest of the day...
I think I'll take the plug I have now, drill it from the inside up but not to the end, then I will make a side drill that will connect to the first one. This way, the plug will actually be able to ventilate the drive.

[cbclemmens]

Mica:
A bad wheel bearing can also make the seal leak - so can a bad wheel hub. I had that happen on my sidecar bike - R 90/6. It was still leaking even with a new bearing and seal. The bore that the bearing race seated into was worn too much and the bearing race didn't properly seat. I had to buy a new wheel.

Craig