Final Drive Leakage

[tkbaker4]

2004 R1150RS, 73K on the odometer, less than 2k my own.
This leak showed up this weekend after a 100 mile ride, probably 300 miles since last washing.
Two questions:
1: Is this a major concern? Bike is behaving excellently.
2: My first impulse was to re-torque the bolt but I don't have the tool to fit the recess. What is the fitting and tool required, and, is there a good package of sizes needed for this bike available.
I guess that's three questions.
All help would be appreciated,
T.
:scratch

[jduke]

It's either the large hub seal or the pinion gear seal. Take the rear wheel off and see if the hub is damp. Hope so because this is the easy one. If the inside hub is dry it's probaby the pinion seal. This one will require more experience. Good luck.

[tkbaker4]

So what tool is required?
Is it a metric or SAE hex? Torx?
Is there a toolkit that includes ALL of the heads I need for these recessed fittings on this bike?
Don't want to bung it up on my first attempt with these...

[Sully]

It's a German product- I have yet to find an SAE fastener on my R1100. I waited for Craftsman to put a set of 3/8" drive Metric Allen wrench sockets and Torx sockets on sale and bought both. I have not yet been at a loss for a wrench....

A little trick I learned from a mechanic at a Chevy dealership: in the absence of a metric Allen wrench- a Torx wrench will usually substitute in a pinch (they're based on metric sizes).

Good luck with that final drive.

[flars]

This leak occurs on a lot of oilheads. Most of the time it is from the pinon seal inside the fd and is only a minor annoyance. It leaks into the rubber boot and then works its way around the boot onto the fd. It can also be from the transmission output seal, which is rare, but does happen.
You will have to determine how bad the leak is. Remove the straps holding the front and back of the rubber boot that attaches it to the fd. Pull the boot away from the swing arm and look up into the tunnel towards the trannie. If it is wet, it is from the transmission output seal and you will have to remove the entire rear end of the bike to fix it. Can't help you there, but someone else probably can.
If the tunnel is dry, the leak is from the pinon seal in the fd, and is the normal leaker. Pull the boot away from the fd and see how much oil comes out. If a LOT of oil, you will have to check the level in the fd to see if it has gotten low, and top it off. There will probably be just a tablespoon or less. Wipe out the inside of the boot and reattach it to the fd. I use a couple of zip ties fastened together to attach the boots on my bike (it takes three ties to go around the front of the boot with the length of ties I have). Clean everything up and ride the bike for a while, keeping an eye out for any major leak. Remove the straps from the boot again, and see how much it has leaked. If it is still mostly dry after a week or so, just keep checking it for the next month or so and do what the rest of us do - live with it. Replacing the seal is normally a dealer repair, and you will save a bunch 'o money if you just take the fd off and take it to the dealer.
If you decide you have to take the fd off you will need a 12 mm allen, a heat gun to loosen the loktite on the pivot pins, and a 30 mm socket in addition to whatever you need to remove the rear wheel.
The pinon seal has leaked on my RS for the last 80,000 miles, so it isn't a big deal as long as it is only a small amount.

[rs36vh]

If it is a leak have it fixed, if it is seepage let it go and keep an eye on the level, on my 2000 rt there always is about a teaspoon or two that gets by the seal or the threads. On advice given to me by an experienced bmw mechanic.

[Gusgus]

I had the same oil for months and finally pulled the F/D and rebuilt it. The oil returned in Dawson City, Canada. I finally after much cost found it was the transmission output seal. It was replaced and now after 22000 not one seep! YEA!
The F/D is not to tough to replace the wheel side seal, but the pinion seal is much tougher.

Best O luck

Gus

[flars]

Another bit of info. If the leak is from the pinion seal in the fd (and it probably is), replacing the seal probably won't be a permanent fix. The replacement will probably start to leak, too - that is why most of us just wipe it down and keep on riding.

[bikerfish1100]

i would recommend that you not go about willy-nilly tightening this or that because you see some fluid leaking onto/out of something. some things can't be moved without sufficient heat, like that pivot bearing bolt. torque specs matter, but that is generally not why a leak exists.
get yourself a shop manual before going into anything on your bike - most like Clymer's or Haynes' (some prefer using both, as there are some inconsistencies between them). Amazon is a good source.

[MotorradMike]

A little trick I learned from a mechanic at a Chevy dealership: in the absence of a metric Allen wrench- a Torx wrench will usually substitute in a pinch (they're based on metric sizes).


Sorry but IMO this is not a good idea. Use the right tool and not a cheap one either. I've had to remove lots of messed up fasteners ruined by people not using the right tools or using the right tools incorrectly.

Tkbaker4 doesn't need to start out on the wrong foot.

Mike

[PGlaves]

Oil seeping at that location at the front of the boot can come either from a leaking final drive pinion seal or from a leaking transmission output shaft seal. In either case there really isn't anything to "tighten". If it a leak that puddles oil then the damaged seal will need to be replaced.

The seal at the final drive pinion is held in place by a large slotted ring that takes a special spanner to remove. Tightening the ring won't make it seal better either. But the ring would need to be removed to replace the seal. It can be done without disturbing the pinion bearing if you decide to go there.

You can get a good idea as to the source of the oil by removing the tie and peeling back the front of the boot. If it is coming from the transmission rearward then you can usually see a telltale stream of oiliness along the entire inside bottom of the swingarm.

If that were my bike I would peel back the front of the boot and thoroughly clean all the oil out of the front of the final drive and the inside of the boot - and obviously off the outside of the boot and swingarm - clean and dry.

Then I would reattach the boot at the front (big wire tie is what BMW uses) and ride a few thousand miles. See if the oiliness comes back. My hunch is you have a little seepage which if cleaned up every 12K service will not get worse for a long time. Voni's R1100S had the same type smear about 20,000 miles ago and I cleaned it up and watch it. So far there isn't enough oiliness to notice.

[Gusgus]

Paul you are absolutely correct.

It took me quite some time to nail the leak from the trans output shaft.

In fact after I replaced the pinion seal, and the large bearing and associated seals and the leak continued.

I was still on the fence of exactly where it was coming from.

It had to grow in enough quantity for me to find the F/D oil level never dropped before I was 100% sure it was the Tranny.

The swingarm never looked as if oil had been flowing down it and the spline was still "just grease" not washed or cleaned.

The other symptom I expected was the forward boot, should have had oil pooled in it. It never did.

After the output shaft seal was replaced, the leak, wet seepage and ugliness was gone.

Oil seeping at that location at the front of the boot can come either from a leaking final drive pinion seal or from a leaking transmission output shaft seal. In either case there really isn't anything to "tighten". If it a leak that puddles oil then the damaged seal will need to be replaced.

The seal at the final drive pinion is held in place by a large slotted ring that takes a special spanner to remove. Tightening the ring won't make it seal better either. But the ring would need to be removed to replace the seal. It can be done without disturbing the pinion bearing if you decide to go there.

You can get a good idea as to the source of the oil by removing the tie and peeling back the front of the boot. If it is coming from the transmission rearward then you can usually see a telltale stream of oiliness along the entire inside bottom of the swingarm.

If that were my bike I would peel back the front of the boot and thoroughly clean all the oil out of the front of the final drive and the inside of the boot - and obviously off the outside of the boot and swingarm - clean and dry.

Then I would reattach the boot at the front (big wire tie is what BMW uses) and ride a few thousand miles. See if the oiliness comes back. My hunch is you have a little seepage which if cleaned up every 12K service will not get worse for a long time. Voni's R1100S had the same type smear about 20,000 miles ago and I cleaned it up and watch it. So far there isn't enough oiliness to notice.

[tkbaker4]

Oil seeping at that location at the front of the boot can come either from a leaking final drive pinion seal or from a leaking transmission output shaft seal. In either case there really isn't anything to "tighten". If it a leak that puddles oil then the damaged seal will need to be replaced.

The seal at the final drive pinion is held in place by a large slotted ring that takes a special spanner to remove. Tightening the ring won't make it seal better either. But the ring would need to be removed to replace the seal. It can be done without disturbing the pinion bearing if you decide to go there.

You can get a good idea as to the source of the oil by removing the tie and peeling back the front of the boot. If it is coming from the transmission rearward then you can usually see a telltale stream of oiliness along the entire inside bottom of the swingarm.

If that were my bike I would peel back the front of the boot and thoroughly clean all the oil out of the front of the final drive and the inside of the boot - and obviously off the outside of the boot and swingarm - clean and dry.

Then I would reattach the boot at the front (big wire tie is what BMW uses) and ride a few thousand miles. See if the oiliness comes back. My hunch is you have a little seepage which if cleaned up every 12K service will not get worse for a long time. Voni's R1100S had the same type smear about 20,000 miles ago and I cleaned it up and watch it. So far there isn't enough oiliness to notice.
I hope to open the boot on Friday and ride this weekend.
Paul, you are, once again, the voice of reason. I will open it, clean everything in and out, and see what happens. Everyone else has help put some of this in perspective for me.
I don't use the wrong tool for the job unless I need a BFH for attitude adjustment.
I realized as this thread went on that in all the money I had invested in tools for this baby I had neglected the External Metric Hex and Torx sockets. They are on their way. Hopefully in the assortments all the right sizes appear. I'll let everyone know what I find and if I find it interesting or intimidating, I'll post pics.
Ve Vill not be intimidated! :german