Driveshaft carrier lube migration

[Justin B.]

I appear to have the dreaded lube migration issue on my R100.  Or, maybe this is happening because it just sits and rarely gets ridden anymore?

Has anybody changed this plastic washer thing on the input of the final drive?  Any gotchas?

[donbmw]

Justin

I don’t remember any plastic washer when I redid my final drive on my R 90/6.

[Bob_Roller]

I watched a shop replace the shaft seal on the final drive on the '82 LS, only saw a typical oil shaft seal .
Also the manual recommends using some sort of thread sealer on the nut that holds every thing together, I guess oil can pass though via the threads on the gear .

[georgesgiralt]

Hello !
Actually there is a gasket under the nut on the input spindle.
It is obvious when you look at it as the spindle is not circular, so you need to seal the grooves.
It's p/N is 33121233302 and is # in the RealOem view which I can't download to show here. l
If you want to change this gasket and the lip seal in the castellated nut, you need a mean to hold the coupling gear steady while you remove the central nut, then have the proper castellated nut tool to remove the nut blocking the bearing and renew the lip seal it holds.
It is not difficult IF you can get a hand on proper tools. bear in mind that you MUST torque the nuts when putting them back in place ! They are used in the play adjusting process, so torque is important. 
While you are at here, you may want to change the two lip seals on the big crown. The outer one is obvious as it seats on the cover.  but the smaller one is at the bottom of the shaft under the crown and under the needle bearing. So you need to remove the needle bearing. It is somewhat easy provided you have an electric heater gun.
Remove all you can (the crown ) and then set the box facing down on the work space. Start heating the rear drive evenly and in a circular motion. The aluminum will expand faster that the steel the needle bearing is made of. So at some point you will hear the bearing falling on the work surface. Done. Install in reverse having the bearing as cool as you can.
Work slowly and with care this is easy to do. no need to re-shim as you put all the same parts back where they belong.
Hope this helps.

[Barry]

I had oil migration from the drive shaft to the final drive. Reducing the driveshaft fill from 150cc to 100cc seems to resolve the problem. Snowbum says even 50cc is enough so my 100cc  feels safe.

[Tony Smith]

Short of doing the seal replacement you can try takign the final drive off and then packing the coupler area whre the driveshaft meets the final drive with as much grease as you can fit in there.

That stopped a persistent oil migration problem  I had.

As far as replacing the seal goes.

Not a big job as these things go, but you will need some dreaded "special tools" and you will need to buy a complete gasket and seal kit on the simple expedient that if one seal has failed, the others will not be far behind it.

Remove the final drive, remove the cover (two 5mm  bolts are used to gently press it off.

Then you need a special tool to lock the crown wheel. The first one of these I did I used the old mechanics trick of stuffing rag into the crown and pinion to jam it, I now think that this is a moderately bad idea on a sand cast final drive and an extremely bad idea on the later investment cast ones, the reason is that you are putting a lot of force into areas that were not designed to be forced and you may well break out the rear bearing in the pinion shaft.

Buy or borrow the special tool to lock the crown and pinion.

Then using a socket and a long extension (or and air wrench) remove the nut that retains the input coupler from the nose of the pinion shaft.

I am a bit hazy on the next step but I think you need another special tool (or an adapted equivalent) to undo the seal carrier, then you replace the seal and reverse.

Whilst you have it apart do check the pinion shaft bearings, frankly these don't tend to fail very often as they are pretty big for the amount of power transmitted and are very well lubricated, water of course will kill them. Getting the rear pinion bearing  out (if you need to) is a matter between you and any god(s) you may believe in. In theory you remove the retaining grub screw and it slides out.

In theory......

The two remaining  bearings and their seals are straight forward, it helps to put the big seal in if you have the tool that does the crankshaft end seal, the back side of the tool is just the right size.

An aluminium beer can (at least the Australian variety at any rate) is the perfect size for slipping over the output coupler so those razor edged worn dogs do not cut your nice new seal to shreds.

I bought mine from www.cycleworks.net

[DadsR65]

I appear to have the dreaded lube migration issue on my R100.  Or, maybe this is happening because it just sits and rarely gets ridden anymore?

Has anybody changed this plastic washer thing on the input of the final drive?  Any gotchas?

I had to take all these parts off to helicoil a stripped drain plug.  This may help:

https://advrider.com/index.php?threads/new-airhead-project.1260761/page-3#post-33692161

[Justin B.]

Well, the reduced capacity and grease packing method are sounding pretty good to me right now!

[Tony Smith]

Well, the reduced capacity and grease packing method are sounding pretty good to me right now!

To be honest, I'd try that first. The day my R65's rear seal failed - the big one at the wheel coupler, I lowered the oil level so that it would not spew oil all over the RHS of the tyre as I went down the range to get home. i reckon that providing there is still enough oil so that the bottom most teeth of the crown wheel are immersed then there is probably enough oil for lubrication. Possibly not enough for cooling, but enough for lubrication. It didn't leak a drop in the 110km home trip, i stopped a couple of times and re-measured the oil level and I did notice that it was warmer than usual.

I'm sure there would have to be someone near you who has the two special tools you need, and one of those - the 41mm slotted nut driver, you could make yourself. So, if you did that, then the right tool to lock the crown wheel is not so big a thing to swallow.

Would you like me to post a picture of the slotted  nut driver so you can decide whether you want to crack on and make your own?

[Justin B.]

Tony, yeah, it would be interesting to look at what it would take.  But, to be honest the older I get the lazier I get so if I can "fix" this with 50 ML of lube in the DS carrier I'll be happy as a clam!

[Tony Smith]

Tony, yeah, it would be interesting to look at what it would take. 

Ok then, here we go.

The Seal carrier removel tool is simply a 42mm nut with 4 corners machined off and drilled to take 4 square headed bolts.  Whilst I would not like to try and make this with a hacksaw and file, it woud be doable, a nuice wet/cold Sunday would suit.

The crown wheel lock is however a cat of a different colour, that is good quality steelm carefully machined. I'd say that a mill would be the only time econimical way of making one, although at a pinch you could use an arbor press and tooling to cut the teeth shapes. It would take a while though.

[Tony Smith]

and the lock

[Justin B.]

Yeah, the seal carrier tool would be pretty easy but you are right about the other one.  I think the reduced capacity "fix" is sounding better all the time.

Thanks for the pics.

[georgesgiralt]

You can make a suitable locking device by cutting out a used driveshaft spindle and welding a steel bar on it... Will fit perfectly as they where made one for each other ;-)