Final Drive seepage

[RoSPA_man]

Quote

Hi all

My 2013 RT's FD developed a seepage/small leak which was chucking some oil from the FD on to the rear wheel rim while on a road trip in France this week. Roadside repair - I drained the oil so as to know what had been lost (I extracted about 150ml) and then put in 200ml to get me home. So it had only leaked about 30 ml of the 180ml put in about a year ago. It seems to seep not at all times but intermittently eg when the air temperature was high and the riding at its shall we say 'most progressive'. Trundling along first thing in the day and it seemed not to happen - at least to any great extent. 

 

I'm now home and the FD didn't seize up or lose much of the 200ml (I think anyway!) . The seepage /leak appears to be from the inner seal ie it is coming from what I thought was a gasket (11 in pic attached) between the two faces of the FD casing. When I look at the microfiche though, I see that what i thought was a gasket is in fact one or more shims - see pic (part #11) and that the sealing function seems to be done by a regular large o-ring (part #8 in microfiche pic attached)

Having looked at several Youtube videos, I'm left with a couple of questions, which are:

1. Is it straightforward to split the FD once it is on the bench - ie any special tools needed?
2. Can I just replace the large O-ring seal and button it up or do I need to consider a change of shims - or are the shims' thicknesses determined at the factory during manufacture and don't change?
3. any gotchas I should know about?

Thanks as always! 

 

 

 

[dirtrider]

32 minutes ago, RoSPA_man said:

Hi all

My 2013 RT's FD developed a seepage/small leak which was chucking some oil from the FD on to the rear wheel rim while on a road trip in France this week. Roadside repair - I drained the oil so as to know what had been lost (I extracted about 150ml) and then put in 200ml to get me home. So it had only leaked about 30 ml of the 180ml put in about a year ago. It seems to seep not at all times but intermittently eg when the air temperature was high and the riding at its shall we say 'most progressive'. Trundling along first thing in the day and it seemed not to happen - at least to any great extent. 

 

I'm now home and the FD didn't seize up or lose much of the 200ml (I think anyway!) . The seepage /leak appears to be from the inner seal ie it is coming from what I thought was a gasket (11 in pic attached) between the two faces of the FD casing. When I look at the microfiche though, I see that what i thought was a gasket is in fact one or more shims - see pic (part #11) and that the sealing function seems to be done by a regular large o-ring (part #8 in microfiche pic attached)

Having looked at several Youtube videos, I'm left with a couple of questions, which are:

Is it straightforward to split the FD once it is on the bench - ie any special tools needed?

Can I just replace the large O-ring seal and button it up or do I need to consider a change of shims - or are the shims' thicknesses determined at the factory during manufacture and don't change?

any gotchas I should know about?

Thanks as always! 

Afternoon  RoSPA_man

 

#11 is not a gasket it is the adjustment shims, IF it is actually leaking from #11 then your leak is probably caused by a leaking "O" ring #8.

 

If it is #8 then you can remove the side cover (with the spool still installed in it), you can do this with the final drive still on the motorcycle. (no need to remove final drive) 

 

But the usual leak point is seal #6 & THAT is more difficult to replace as you need heat, a special flange puller (or a gear puller & ingenuity). Then you need to (evenly) re-heat to specific temperature then use a special installer ( sometimes you can just heat & slide on/tap on), but if it stops short of going all the way on then you have to work quickly with an installer. (again no need to remove the final drive from motorcycle)

 

If it is just the #8 "O" ring then not  a big deal to do yourself. If it's the #6 seal then that is not a do-it-yourself unless you have proper puller/installer, a way to get the flange evenly heated (without overheating), proper tools to do the job. 

 

Before going too far into it make sure that your final drive vent is working correctly, BMW came out with an updated rubber vent (breather) cap.    P/N-- 33748864458 Breather

[DakarTimm]

Not to hijack this thread . How differant is this final drive from a 2005 R1200RT ? My brothers bike is exhibiting the exact same symptoms 

[dirtrider]

1 hour ago, DakarTimm said:

Not to hijack this thread . How differant is this final drive from a 2005 R1200RT ? My brothers bike is exhibiting the exact same symptoms 

DakarTimm

 

The 2005 hexhead drive is slightly different that the later camhead drive. About the same on the "O" ring replacement but the seal & crown bearing are different.  

 

Plus, the 2005 doesn't have a vent (breather) so fluid level is critical, do not overfill it as that usually forces a leak. The amount was revised down to 180 cc. 

[RoSPA_man]

22 hours ago, dirtrider said:

Afternoon  RoSPA_man

 

#11 is not a gasket it is the adjustment shims, IF it is actually leaking from #11 then your leak is probably caused by a leaking "O" ring #8.

 

If it is #8 then you can remove the side cover (with the spool still installed in it), you can do this with the final drive still on the motorcycle. (no need to remove final drive) 

 

But the usual leak point is seal #6 & THAT is more difficult to replace as you need heat, a special flange puller (or a gear puller & ingenuity). Then you need to (evenly) re-heat to specific temperature then use a special installer ( sometimes you can just heat & slide on/tap on), but if it stops short of going all the way on then you have to work quickly with an installer. (again no need to remove the final drive from motorcycle)

 

If it is just the #8 "O" ring then not  a big deal to do yourself. If it's the #6 seal then that is not a do-it-yourself unless you have proper puller/installer, a way to get the flange evenly heated (without overheating), proper tools to do the job. 

 

Before going too far into it make sure that your final drive vent is working correctly, BMW came out with an updated rubber vent (breather) cap.    P/N-- 33748864458 Breather

As always, Dirt Rider, thanks for your invaluable help. I guess the obvious thing to do is to try the "#8 route" and then hand the FD to a pro if "#8 route" doesn't work!

I've just ordered the seal - I'll let you know how it goes

Thanks once again

[RoSPA_man]

On 5/23/2024 at 4:12 PM, dirtrider said:

Afternoon  RoSPA_man

 

#11 is not a gasket it is the adjustment shims, IF it is actually leaking from #11 then your leak is probably caused by a leaking "O" ring #8.

 

If it is #8 then you can remove the side cover (with the spool still installed in it), you can do this with the final drive still on the motorcycle. (no need to remove final drive) 

 

But the usual leak point is seal #6 & THAT is more difficult to replace as you need heat, a special flange puller (or a gear puller & ingenuity). Then you need to (evenly) re-heat to specific temperature then use a special installer ( sometimes you can just heat & slide on/tap on), but if it stops short of going all the way on then you have to work quickly with an installer. (again no need to remove the final drive from motorcycle)

 

If it is just the #8 "O" ring then not  a big deal to do yourself. If it's the #6 seal then that is not a do-it-yourself unless you have proper puller/installer, a way to get the flange evenly heated (without overheating), proper tools to do the job. 

 

Before going too far into it make sure that your final drive vent is working correctly, BMW came out with an updated rubber vent (breather) cap.    P/N-- 33748864458 Breather

 

Hi DR

Well, I decided to tackle the FD to replace the seal #8 - with the FD still in place on the bike.

 

However, having removed the 10 bolts, I decided to stop and ask a few questions before proceeding because I'm not sure on a few points, which i will mention below

• when you say remove the side cover of the FD with the spool still on, does that mean that having loosened the 10 bolts around the perimeter, I should then be able to remove the cover while still leaving the brake disc and spool (which I take to be the piece that holds the rear wheel) still on the fd cover?
• with the 10 bolts removed, should it be a case of tapping the cover off or does it need some serious force and /or heat applied to split the FD? Because I'm not sure what is supposed to come out when the cover separates, does it perhaps need to be hit hard from the other side? I tried a few gentlish taps on the cover where the brake caliper is held, but nothing seemed to want to move, so rather than break something, it's often better to pause!
• Pic attached

 

[dirtrider]

5 hours ago, RoSPA_man said:

 

Hi DR

Well, I decided to tackle the FD to replace the seal #8 - with the FD still in place on the bike.

 

However, having removed the 10 bolts, I decided to stop and ask a few questions before proceeding because I'm not sure on a few points, which i will mention below

• when you say remove the side cover of the FD with the spool still on, does that mean that having loosened the 10 bolts around the perimeter, I should then be able to remove the cover while still leaving the brake disc and spool (which I take to be the piece that holds the rear wheel) still on the fd cover?
• with the 10 bolts removed, should it be a case of tapping the cover off or does it need some serious force and /or heat applied to split the FD? Because I'm not sure what is supposed to come out when the cover separates, does it perhaps need to be hit hard from the other side? I tried a few gentlish taps on the cover where the brake caliper is held, but nothing seemed to want to move, so rather than break something, it's often better to pause!
• Pic attached

 

Morning  RoSPA_man

 

Did you remove the black plastic seal cover on the non-brake disk side of the final drive? 

 

Once that seal protector is removed, then use something to drive the spool out from the non brake disk side. Don't use anything made of steel. I have a rubber mallet that is about the size of the spool axle. I hold that against the spool axle on the non disk side then strike the rubber mallet with a big hammer. 

 

If you use wood make sure it is hard wood that won't splinter & ruin the seal.  

 

You might even have to heat the final drive housing just inboard of the side cover (about where the "O" ring sits). 

 

You can tap on the brake caliper mounting area a little  but use a soft hammer (or hard wood) & don't beat on it with a lot of force as the cover needs to come out straight not angular. 

 

Don't over force things, if it is really stuck then you can damage the bearing or cover. 

 

Some come right out & others will fight you. Just don't pry on the housing & damage anything. 

 

Check the rear wheel speed sensor "O" ring while you are there as those can also leak if the sensor was removed & replaced in the past.

[EdM]

Personally I'd be very surprised if the leak was from the o-ring as it is not something that once installed, is likely to fail. Even if it was leaking it would be more of a trace weeping type leak not what you have shown. I would be more inclined given the history of failures with these FDs that it is the large main seal (#6) that is the source of your leak and the bearing (#9) is failing causing that. There should absolutely zero play in that bearing and it should be smooth to rotate. You will need to disassemble the FD as you have begun for those parts to be replaced so no harm in continuing as you are. The issue though is, you will need special tools to remove the flange and to get the bearing off the crown gear. 

[dirtrider]

12 minutes ago, EdM said:

There should absolutely zero play in that bearing and it should be smooth to rotate. 

Morning EdM

 

There is usually a little play even in a normal bearing. BMW gives a spec of up-to just under 1/4" of movement on a cool/cold drive.

 

The Hexhead gives even more play as normal. The camhead/hexhead is different than the older 1100/1150 drives as the camhead spool floats so there is no way to shim the bearing preload (it is all in the bearing C factor & that has a range). 

[EdM]

I know BMW allows a small amount of play in the bearing, but my experience has taught me that once there is measurable play, bearing failure is headed your way and continual monitoring is advisable to prevent being stranded when it happens. 

 

The actual measurement is 1mm total movement at the wheel rim at 35 C. Scan2024-05-31_102642.pdf

[RoSPA_man]

All good - all really interesting and useful.

I checked the vent (see pics) and blowing through it , it does seem to be fine with no issues. With no part number, it's hard to tell if it is the latest

Pondering on this some more,  eg that I rode about 800 miles from mid-France to the UK without any leak at all and that the drained oil looks fine too (quality and quantity),  think that as I haven't gone too far, I'm going to button everything back up, clean everything scrupulously where the seepage was, then run it for a week or two to see what if anything leaks.
I'm also toying with the idea of buying a warrantied used FD which might in the end be cheaper (~£250) and quicker than a lot of work on the FD. (Latest plan)! 

Wish me luck!

Do either of you happen to know the torque setting for the 10 bolts around the perimeter of the FD? 

Rospa_Man

[dirtrider]

54 minutes ago, RoSPA_man said:

 

I checked the vent (see pics) and blowing through it , it does seem to be fine with no issues. With no part number, it's hard to

Do either of you happen to know the torque setting for the 10 bolts around the perimeter of the FD? 

Rospa_Man

Morning Rospa_Man

 

30 nm