Questions about R11S transmission output shaft seal replacement.

[pwillikers]

In an attempt to make replacing the transmission output shaft seal as noninvasive as possible, I have a few questions for those who have gone before...

1. Is it correct that to access the transmission output shaft seal for replacement all one needs to do is remove the swinging arm and the drive shaft from the transmission output shaft and the seal can then be accessed/replaced with the transmission still in place?
2. Does the (stock) exhaust/cat need to be removed to remove the swinging arm?
3. Does the rear drive need to be detached from the swinging arm to remove the swinging arm/drive shaft from the transmission? I'll probably disassemble it anyway but I am curious if the process could be simplified by removing the whole ass end intact.

[wswartzwel]

if you remove the pivot pins, and pop the front yoke off the output shaft, you can move the swing arm/ wheel assy backward. should be enough room to put a screw in the seal and pull it out. Removing the exhaust first would be a good idea. It has been several years since I have pulled an S apart, so my memory has faded.

[pwillikers]

Thanks very much Bill for sharing your wisdom and experience.

[RBMann]

Yes, you can pull the whole assembly but I have never been able to get the driveshaft u-joint clipped back on the output shaft with it inside the swing arm.

[pwillikers]

Today I finally got after it. This saga began when oil appeared on the bottom of the paralever tube, rear drive and rear wheel.



I pulled the S apart fully expecting to have to replace the transmission output shaft seal.



What I found however was that the paralever tube was clean inside. This would indicate that the transmission output shaft seal is fine.



Maybe it's the engine main shaft output seal or the transmission input shaft seal? I pulled the starter to have a look around the clutch. Nope. Dirty but no oil at all.



So where is this oil coming from? Here's the underside of the transmission. It sure looks like it's coming from either the transmission drain plug or the seam where the transmission cases halves mate. I feel like a dope for not doing more preliminary investigation and just jumping to the conclusion that the transmission output shaft seal was bad. Oh well, onward and sideways.



Just to be sure it's not the transmission case (which I think likely), I checked the torque on the 10mm transmission case bolts.


(Props if you recognized the SV650 in the background.)

All the case bolts I could get to were seated but not torqued tightly at all. I know they're only 10mm and shouldn't be reefed on so I just snugged them all a slight bit more, less than an additional eighth turn. Most of the case bolts are inaccessible since the transmission is assembled off the bike. There were two on the underside of the transmission I could see but couldn't quite get to so I Rube'd up this custom socket contraption to get to them. It actually worked pretty well and is kinda comical so I thought I'd share.





I then pulled the transmission drain plug. It was ridiculously tight requiring serious grunt on the end of a 24" breaker bar. There was no crush washer. Why is there no crush washer? REALOEM shows none but the Bentley Manual says different. I tend to believe REALOEM.





It seems to me that there should be a crush washer (especially since this may be the source of my leak). I'd like to see if installing one will stop the leak. I rooted around REALOEM looking for one to no avail.

Anyone know the part number of one that'll fit or better yet have one they'd part with?

Am I missing something? Any other suggestions as to the source of the leak?

Thanks, Paul.

[flatbutt]

IIRC it could be leaking from where the shaft and the final drive meet as well.

[wswartzwel]

Most common leak to cause oil residue where pictured in first image is the pinion seal in the final drive. Very easy fix, I have done several of them for customers. Take the final drive to Roger Albert and he can take care of it for you.

[pwillikers]

Thanks Bill, Would you see oil all over the bottom of the transmission (like in the pic) if it were the pinion seal?

[wswartzwel]

No that is something different. Pull the clutch slave cylinder to make sure it isn't leaking. But to me the oil on the bottom looks like a drain plug that needs a new sealing washer.

[pwillikers]

According to the manual there may or may not be a sealing washer and I couldn't find a P/N anywhere. Mine didn't have the washer. I'll go to Autozone with the drain plug and see if they can find one for me.

[tjs]

There is no seal ring for the Transmission drain plug on an R1100S . Drain plug torque = 55 Nm (40 ft. lb.)
tjs

[pwillikers]

I couldn't find an appropriately sized crush washer anywhere locally so I finally bought ten from ebay (shipped from Israel of all places) I.D. 26mm O.D. 32mm. Here it is happily ensconced. Notice the absolute lack of new crud. I still have trouble believing that that much oil leaked from around the drain plug, but, the crush washer certainly seems to have fixed the leak. :-)

[flatbutt]

Well we all know that just a wee bit of oil can go a long way to making a mess. Those cases sure are clean

[JackH]

Hey Paul, how has your R11S been over the last year? Any further leaking? I'm facing the identical crud around the bottom of the transmission, near the drain plug. So naturally I'm curious whether or not yours has been good after you snugged everything up.

[mosearch]

I am going to add to this thread rather than start a new one...

I suspect I have an output seal leak...see photo below. The blue stuff is transmission oil (Redline). It's dripping on to the cat. Smells bad when I stop; but not leaking great quantities...drain plug is clean and dry.

Is my output shaft seal guess correct? How difficult is the repair? Any good tutorials?