Oil leak from output shaft GS1100G

[Guest]

I noticed oil leaking from the output shaft flange (#11) that the driveshaft bolts to. It is actually seeping out the center of that flange. I have done numerous searches and couldn't find much on the subject. The only seal that I see on parts fiche is #15 in the pic below. Is this the most likely culprit and if so what is involved in replacing it? It appears that I should just be able to remove the center nut, pull the flange and replace the seal but I just wanna make sure theres not another detail I may be missing.

Thanks, Mike

[Nessism]

There are a number of different threads in the archives where members here have had to change the secondary drive driven gear due to breakage on the 1100G and 650G (same part you need to remove). You should be able to find a number of useful threads using the search function. I've never performed this repair so can't offer any direct advice.

This one should get you started.

http://www.thegsresources.com/_forum/showthread.php?t=200119

[bwringer]

Unfortunately, it's probably not just a seal.

Many times, one or more of the bearings (#15 most likely, and/or #7) is going bad. This allows the output shaft to move and causes the leak.

There have also been several cases where the threaded end of the shaft (#1) has broken off. The bike will still move, but the flange can move around on the splines and leads to leaks. This can be fixed by drilling and tapping the shaft for a socket-head bolt.

You'll have to get it out of there and see what's going on.

[willie]

Unfortunately, it's probably not just a seal.

Many times, one or more of the bearings (#15 most likely, and/or #7) is going bad. This allows the output shaft to move and causes the leak.

There have also been several cases where the threaded end of the shaft (#1) has broken off. The bike will still move, but the flange can move around on the splines and leads to leaks..

X2 I've seen this happen twice myself. I suggest you drain the secondary oil, if you haven't done so already, and have a look. I bought an 1100G several yrs ago that made a huge racket. I drained the secondary oil and it looked like metalflake coal black paint. The bearings were shot and the excessive radial play caused the seal to leak. I ended up replacing the entire cluster. I had another 1100G with the broken output shaft bwringer described. Made some noise at low speed but all else was fine. I didn't know what it was until after riding the length of Rte 66 and back to NC with it like that.
Good luck,
Willie

[matt1100]

No telling till you get a good look at it. Removing it isn't a small task, either. Best way I found: remove swing arm (a few other things gotta come off first of course); unbolt/loosen motor mounts and get rear of motor to tilt up just a little; loosen the engine case mating bolts in the area surrounding the chunk to relieve some pressure; undo the four bolts and gently pry it out; post an update here. These shafts are great when they are operating correctly, PITA when they do not.

[Paul]

I have the same problem on my project 1100GL, so I will be following this thread with interest...good luck!

[motomike]

Good news is the engine is already out of the bike. I gotta check the shaft for movement and see what I got. When I rode it before disassembly I didnt have any abnormal noise so I cant see it being all that bad but the oil is definately coming from somewhere in this area. Thanks to all that have replied so far for the advise. Updates to follow.

[motomike]

Ok I took the secondary driven gear assembly out last night to have a look (which was surprisingly easy btw). The bearings felt a little sloppy but there were NO signs of scoring or excessive heat, they looked great. Before I took it apart, the shaft had no play whatsoever and I couldnt hear any bearing noise at all. Its almost like the oil is coming out between the u-joint flange and the gear shaft. Any ideas anyone??

[dr_puter]

Shaft Leak

I too have a leak and will be following this thread. If you could post some pictures during your process I am sure it will help those of us in the same situation. I have to replace exhaust at the same time, so I will probably be removing the entire rear end when I do mine.

[motomike]

On another note, it was leaking from here before I removed the engine and it has also continued to leak while engine is out of the bike. I have read a lot about overfilled secondaries causing leaks but would it leak from where I'm describing? Just a thought.

[matt1100]

Nah, overfilled secondary comes out the "mystery hole"(beneath the starter via the breather hose). Have you checked bearing preload? If its too "free" it may just need the shims may just need to be a hair narrower to "tighten" the assembly back up. Maybe the seals just need replacing. I'd strongly consider the bearings though. You'll need a new nut too. On reassembly you'll have to check preload and mesh depth, but your existing shims may all work out fine.

[motomike]

Nah, overfilled secondary comes out the "mystery hole"(beneath the starter via the breather hose). Have you checked bearing preload? If its too "free" it may just need the shims may just need to be a hair narrower to "tighten" the assembly back up. Maybe the seals just need replacing. I'd strongly consider the bearings though. You'll need a new nut too. On reassembly you'll have to check preload and mesh depth, but your existing shims may all work out fine.

I dont have a dial indicator to check free play but before I took it apart everything felt really good. Hardly any slack at all. However, I think since its already apart I will go ahead & replace bearings & seals as a precaution, especially since there have been so many stories about them failing with catastrophic results.