final drive leak on 03 1150rt

[detour]

hello to all,i am new to the forum so hopefully this isnt a recently asked question.i just got back from riding some demo bikes at daytona but i stopped half way home,about 130 miles of 90mph at a rest stop and when i came out i noticed it again,yes again,oil dripping from the hole in the center of the lugnuts,only when on the side stand.i should back up a little,this happened about 3 weeks ago on a 230 mile ride with my wife while riding two up.no problems all day but when i got home and parked in the driveway on the center stand i noticed oil dripping in the same place,center of the lugnuts.i took the rear tire off and inspected final drive and took cover of final drive and looked around but it looked o.k.common sense tells me its the seal in final drive which may i add had to be replaced along with the final drive bearings as they went bad on me back in nov.07.got lucky and that pretty much happened pulling into my driveway.anyway the bearing sounds fine now but i did notice the tapered roller bearing is loose but in good shape.i know it should not be loose on the ring gear.i am thinking of putting a new tapered bearing and seal in and hope the new bearing fits tight enough to stay firm and that be the end of it.i am appologive if it seems i am rambling but i wanted to give enough info for a good response hopefully.help! i love this bike but i am not feeling that dependability i used to.p.s. i should also say it seems to occur only after a fairly lenghty ride both times but not on 30 or 40 mile rides

[awagnon]

Have you looked at the FD oil to see if there are any metal flakes in it. The bearing or bearings may be failing again which would lead to a seal failure. The ring bearing may not have been preloaded properly or something else which would cause premature failure. Or just a bad seal as you suspect.

 

Did a BMW shop do the work? If so, it should be under some kind of warranty.

[ShovelStrokeEd]

It could be as simple as a clogged breather and an overfill of final drive lubricant.

 

There is a little breather located on the top of your final drive, remove it and be sure the passage is clear.

 

Drain the final drive fluid and have a really careful look at what comes out. Put on some rubber gloves and swirl the drained fluid with your fingers under strong light. Look for any "shine" in the fluid. If you see some, you have a problem.

 

Your bike is out of warranty but the repair may not be.

[T__]

hello to all,i am new to the forum so hopefully this isnt a recently asked question.i just got back from riding some demo bikes at daytona but i stopped half way home,about 130 miles of 90mph at a rest stop and when i came out i noticed it again,yes again,oil dripping from the hole in the center of the lugnuts,only when on the side stand.i should back up a little,this happened about 3 weeks ago on a 230 mile ride with my wife while riding two up.no problems all day but when i got home and parked in the driveway on the center stand i noticed oil dripping in the same place,center of the lugnuts.i took the rear tire off and inspected final drive and took cover of final drive and looked around but it looked o.k.common sense tells me its the seal in final drive which may i add had to be replaced along with the final drive bearings as they went bad on me back in nov.07.got lucky and that pretty much happened pulling into my driveway.anyway the bearing sounds fine now but i did notice the tapered roller bearing is loose but in good shape.i know it should not be loose on the ring gear.i am thinking of putting a new tapered bearing and seal in and hope the new bearing fits tight enough to stay firm and that be the end of it.i am appologive if it seems i am rambling but i wanted to give enough info for a good response hopefully.help! i love this bike but i am not feeling that dependability i used to.p.s. i should also say it seems to occur only after a fairly lenghty ride both times but not on 30 or 40 mile rides

 

 

Brad, if your (new in Nov) bearing is again loose you definitely have a problem there..

 

Those bearings don’t usually -come loose- on the ring gear but instead have the bearing balls wear or the ball separator wear causing that looseness you now have,, it also shows up as a seal leaking gear oil..

 

You might visit your local BMW dealer as there have a lot of problems with those rear bearings,, maybe they will warranty that bearing for you..

 

Seeing as you have failed one bearing,, sounds like you have failed a 2nd bearing I wouldn’t JUST pop another bearing & seal in there as those bearings are precisely set to a given PRELOAD.. It sounds like maybe the first bearing was just popped in the housing with no measurements or proper re-setting taken.. If you don’t measure the preload & re-set that you will probably fail another bearing (maybe this time when you are on the road & away from home somewhere).. It isn’t an easy job to set that deep groove bearing preload at home without precision measuring tools but can be done with lots of time & persistence..

 

Twisty

[Anton Largiader]

...oil dripping from the hole in the center of the lugnuts...

If this is really the case, you have a bad ring gear assembly. The only way for oil to get into the space behind the lug bolts is if the ring gear is loose on the axle. This jibes with a slight bit of looseness you believe to be in the tapered bearing. It's very rare, but I have seen it.

 

These comments presume that your observations about the tapered bearing and the source of the oil are accurate.

[T__]

...oil dripping from the hole in the center of the lugnuts...

If this is really the case, you have a bad ring gear assembly. The only way for oil to get into the space behind the lug bolts is if the ring gear is loose on the axle. This jibes with a slight bit of looseness you believe to be in the tapered bearing. It's very rare, but I have seen it.

 

These comments presume that your observations about the tapered bearing and the source of the oil are accurate.

 

Anton, I guess I don’t understand what you are saying here.. Can you explain it in a little more detail.. The hub that the ring gear is mounted to is a one piece machinement.. Even if the ring gear was loose on the hub I don’t see how it could cause a leak as the seal is outboard almost out to the wheel attachment area.. Is there something I am not seeing here?

 

 

 

Twisty

[detour]

thanks for your response,as i stated i replaced the the main final drive bearing and seal and the tapered bearing after a failure at approx. 25000 miles.i did not replace the outer race in the final drive though as did not feel comfortable doing so with limited tools.probably a mistake on my part but it seemed to match up nicely.the ring gear where the tapered bearing goes on is just showing slight wear from not being seated on tight which i know it was when i originally put it back together.i should also mention after my leak a few weeks ago i took the drive apart and the bearing was on tight .is there something i am not doing here.i put the new seal in and new main bearing and tapered roller bearing and put it back together and torqued to specs.

[Anton Largiader]

Can you explain it in a little more detail.. The hub that the ring gear is mounted to is a one piece machinement.. Even if the ring gear was loose on the hub I don’t see how it could cause a leak as the seal is outboard almost out to the wheel attachment area..

 

The ring gear and wheel flange are one steel part (I think), and an aluminum axle is pressed into the center of it from the right. If that's loose, oil migrates between them, ending up in the void between the lug holes. If you look into the lug holes, you can see the end of the pressed-in axle.

[T__]

Can you explain it in a little more detail.. The hub that the ring gear is mounted to is a one piece machinement.. Even if the ring gear was loose on the hub I don’t see how it could cause a leak as the seal is outboard almost out to the wheel attachment area..

 

The ring gear and wheel flange are one steel part (I think), and an aluminum axle is pressed into the center of it from the right. If that's loose, oil migrates between them, ending up in the void between the lug holes. If you look into the lug holes, you can see the end of the pressed-in axle.

 

Anton, I’ll be darned.. I have a final drive apart in the shop so went out & looked.. I see what you are talking about (I presume the inner aluminum ring pressed in from the rear)..

 

It looks like that could possibly be pushed loose if lug bolts that were too long were installed & tightened..

 

Thanks,, I hadn’t noticed that before..

 

 

 

Twisty

[Anton Largiader]

It looks like that could possibly be pushed loose if lug bolts that were too long were installed & tightened..

Hadn't thought about that. Good point!

[detour]

thanks again for responding,i am still a little confused as everything except the tapered bearing feels tight but oil was definitely coming out the lug holes when i removed them.but as far as being to long,the are the stock ones that came with the bike so i dont see where the would have a effect

[T__]

thanks again for responding,i am still a little confused as everything except the tapered bearing feels tight but oil was definitely coming out the lug holes when i removed them.but as far as being to long,the are the stock ones that came with the bike so i dont see where the would have a effect

 

Brad, what do you mean by “as everything except the tapered bearing feels tight”? Do you have the final drive pulled apart NOW & notice slop in the tapered bearing rollers to the inner race? If so,, that is normal as that (tapered) roller bearing is only tight when installed into it’s outer race & under correct preload.. If something different please explain it..

 

Now on your leak.. Difficult to say without actually working with it my self.. I guess you have about two possible areas of leakage..

 

_The first would be the big outer oil seal leaking & the gear oil is running down between the wheel & the mounting flange so you see it in the lug bolt area & center hole after you remove the wheel..

 

_The second would be as Anton noted above & that would a seeping between the pressed in inner pieces & the wheel mount hub area.. Difficult to believe it is leaking there without you seeing something loose in the ring gear/hub assembly or signs of movement in the those pressed in pieces..

 

My guess is about all you can do is first look for signs of anything being loose or moving down inside that ring gear hub,, look for signs of that aluminum ring (in my first picture) being out of place or signs that a lug bolt has been screwed in too far at one time & displaced it (look for a contact ring from a lug bolt).. Look for a problem in the places noted by the arrows in the picture below..

 

If nothing found by JUST looking or lightly prying then about all you can do is clean it up REAL GOOD,, especially the inside of that hub hole & lug holes (use brake clean).. Then re-assemble it using a new outer oil seal.. Then re-assemble the final drive,, fill it with gear oil & ride it for a while.. Keep an eye on the area of the outer oil seal & look for signs of leakage.. Then remove the lowest lug bolt & leave it out for a while & look for signs of gear oil leaking from the lug bolt hole.. It shouldn’t take long to figure out if you have an outer seal leaking or the hub itself is leaking down inside between the pressed in parts.. If it is the hub itself leaking about your only recourse is to replace the ring & pinion/hub assembly or find another final drive..

 

Twisty

[detour]

thanks so much for the advise,i will check these asap must go to work now.the tapered roller bearing is actually loose as in able to just remove with no restriction at all.it just sits on there.i will let you know what i find out .thanks again

[T__]

thanks so much for the advise,i will check these asap must go to work now.the tapered roller bearing is actually loose as in able to just remove with no restriction at all.it just sits on there.i will let you know what i find out .thanks again

 

 

Brad, are you saying tapered roller bearing INNER RACE will just slide on & off the hub’s machined bearing mounting area? (that is supposed to be press fit).. If so that IS a ( BIG) problem & shouldn’t be so.. Does it look like the bearing’s inner race has been spinning on the hub?

 

Basically -IF- that tapered roller bearing inner race is loose on the hub you probably have a hub issue in that area.. Does the part the bearing presses on look loose, distorted or worn?

 

 

Twisty

[Boffin]

When the FD was rebuilt last time was the assembly re-shimmed to give correct preloads on the bearings? If the taper bearing was replaced the clearance can change significantly and if the preloads are not correct this will lead to premature failure of the seals and bearings.

 

Andy

[detour]

the ring gear tapered roller bearing outer race is tight inside the case.i however did not change this race when i changed the tapered roller bearing and main bearing on the ring gear.the tapered roller bearing will just pull off and on the ring gear with no resistance.you can see wear on the bearing slightly and the ring gear slightly from it spinning on it when it should not have.i am afraid to ask this but do you know how much a complete final drive might cost

[T__]

the ring gear tapered roller bearing outer race is tight inside the case.i however did not change this race when i changed the tapered roller bearing and main bearing on the ring gear.the tapered roller bearing will just pull off and on the ring gear with no resistance.you can see wear on the bearing slightly and the ring gear slightly from it spinning on it when it should not have.i am afraid to ask this but do you know how much a complete final drive might cost

 

 

Brad, first MAKE DARN sure you have the correct bearing on it now.. Maybe your bearing is incorrect or mis-manufactured..

If the bearing inner bore is the correct size then you have a definite problem & probably a used final drive would be the cheapest way to go…

 

For the life of me I don’t understand how that bearing became loose on the hub.. Was it always like that,, or did someone press on an incorrect bearing,, or did that bearing fail at one time & spin on the hub snout? That bearing being loose on the hub is way out of character for the BMW oil head..

I see you installed a new roller bearing? Was the original one tight when you removed it? If so, was the replacement tight when you installed it? If not maybe you just have a mis-built bearing.. Still doesn't explin the oil leak though..

 

Listed below are a few places to check for a used final drive..

 

 

 

 

 

http://www.beemerboneyard.com/oilheadparts.html

 

http://www.cyclesrecycled.com/

 

http://www.ibmwr.org/market/adlist.php?cat=ops

 

Twisty

[detour]

i talked to a bmw shop in fort meyers today and one mechanic said he has seen the leak i described and was never able to fix it.it required a new final drive.it sounds similar to what antoin was saying because i did a real good inspection and there no way it is the seal leaking for the oil to get where it was with none on the exterior of the seal so to speak.the main bearing still seems fine.i talked to corporate bmw but they made no promises about paying for parts or anything if i take it to a authorized bmw dealership but possibly may do something after the shop manager contacts them because it was all documented about my other bearing failure to.not sure what is next for me but its been 4 days since i have rode and it is driving me crazy looking at my bike not knowing what to do next.

[Anton Largiader]

The situation you describe, with the tapered bearing race loose on the axle, is exactly what happened in the other situation I know of. The axle is loose in the ring gear and in the tapered bearing.

 

The axle is not available separately so the gearset needs to be replaced. It may be possible to repair your gears using the axle from a different gearset, but that's uncharted territory AFAIK.

 

A used FD would be the way to go. Second to that, a used gearset, a new gearset, and worst case a new FD. Let us know what you need; maybe someone can help. I have a 3.09 gearset but I doubt you'd want that. I also have a 2.91 but I have a plan for it so I'm not in a hurry to part with it.

[Anton Largiader]

Here's a photo. You can see the marks where the tapered inner race has moved on the axle.

Photo courtesy RubberChicken

 

[detour]

well guys i cleaned everything up real good and put it all back together but did not get to take a ride yet,darkness set in and want to give a good ride during the daylight and see whats up.everything still feels tight and the lug nuts are original so as far as that issue it should not be the cause but it certainly is leaking from that area.i torqued lugs to specs every time.i let ya know soon,thanks again guys

[detour]

well i took my bike for a 50 mile ride today at interstate speeds and got home and put it on the side stand and no leaks.i removed every lug one at a time and no fluid.i am glad but yet not confident that this is not going to reoccur.i dont remember the last time a problem kind of solved itself.hopefull but still scratching my head.