Time for another transmission oil leak thread

[4corsa]

Decided enough was enough with the slow drip from my 2002 V11 Scura transmission side case onto the crossovers.  I removed the starter and found the leak not coming from the perimeter seal, but from the round bearing-looking items in the middle of the cover (see photo).  So my first question is - what are these?  Are there O-ring seals inside the side cover for them?  If possible, I'd like to order whatever parts i need before i go much further.

Also, what is the large cap nut just in front of the gear selector (see photo)?  That will have to be removed before the side cover comes off - any precautions?  Other than first draining the gear oil, is there anything i need to know before taking that side cover off?  Any help or suggestions (especially from anyone who has removed there side cover) would be greatly appreciated.  Thank you.

 

[AndyH]

The 'round bearing-looking items in the middle of the cover' are the caps on the ends of the shafts for the selector gears. Guzzi don;t seem to list a separate O-ring to seal these these shafts in the parts lists but experienced gearbox surgeons on the forum should be able to tell you whether these seals are user-serviceable in any fashion.

The dome nut is the end of the selector eccentric adjuster. I'd say that if your gearbox is selecting fine at the moment don't touch this. It shouldn't need to be removed in order to remove the gearbox cover.

There are posts on the forum covering replacing the selector pawl spring which should give answers to your questions, including how to remove and replace the cover road-side without draining the oil!!

[jwh20]

My new-to-me '02 LeMans has the same issue.  I see cooked oil residue on top of the crossover and weeping from the same area you show in the photos.

 

I'm hoping to see how this repair goes for you before I tackle it...

[4corsa]

Thanks AndyH. I just read all the Belfastguzzi threads - wow - very thorough and helpful. I did not see those threads when I did read all the other transmission leaks threads. His photos show the gears attached to the inside of the cover. I'm wondering how those come off, if they need to go back in the exact same rotational position, and if there will be any way to seal them. I see that Harper's sell a plate kit ($130) - I wonder if that comes with caps installed and properly sealed. I'll call them Monday and find out. Meanwhile, i'm of course wondering if there is an easier way out and if anyone has had any luck sealing the caps from the outside...

[4corsa]

i found this photo ofo the inside of the side cover and instructions in my service manual (missed it first time around).  Looks doable.

[thumper]

I used a fix that was posted long ago, clean it op good, then three bond a dime in the hole, wait over night and done.

Worked fine for me 4 years ago.

[4corsa]

Tried to find it in your posts, but they only showed your last 4.

Sorry, but not quite understanding your fix. The dime goes on the inside of the cover?

Thanks.

[docc]

I found thumper's "dime fix" post in this thread.  Those shaft ends you see wet are pressed into the side plat and do not rotate. There should be no reason you could not run a bead of, say, JB Weld epoxy around the clean joint and stop and seeping there without removing the side plate.

 

If you elect to remove the sideplate, make sure the gearbox is in neutral when you take the plate off. You'll see index marks on the the toothed selector plates to confirm the neutral position of the shift mechanism.

[andy york]

gearbox is popular these days. I cleaned mine up the other day and just ran a bead of sealer all the way round. Then fingered it to smear around and cover all of the shaft.

Taking the side plate off is kinda useless if you can seal it from the outside, but to each his own.

Some of the gear selectors were indexed some not. Some pairs have more teeth than other pairs. like Docc says, If you pull the cover,make sure your in neutral

Now off to the output shaft seal  

[thumper]

On the outside, you can just use some black silicone on the outside of the dime to match your case cover.

I just put in a bead of 3bond then pushed in the dime smeared some more on the outside and its been no problem. 

[4corsa]

So i did the deed - not my proudest moment of repairs, but i'm guessing it will work.  Plus its completely hidden by the starter and cover.  I used J-B Weld Original Cold-Weld Steel Reinforced Epoxy.  I pushed it into the perimeter recess with my finger best i could and then just smoothed it across the middle. 

Please note that there were two types of this epoxy at the hardware store.  This one is rated for 550 degrees, while the other was only rated for 220 degrees - pays to read the back of the package.

 

[4corsa]

Thanks very much to docc, thumper, AndyH, and Andy York for your help. So great to have back up on these repairs!

[4corsa]

Follow up report - took the Scura for a spirited ride over the weekend and after the first 50 miles, no leaks. But victory was short lived - another 50 miles and back in my garage I smelled the all too familiar aroma of gear oil burning on my crossover. The good news is it wasn't coming from the newly sealed shaft bosses, but now coming from the hole with the bolt head midway between the sealed bosses and to the left (see photo above). I double checked my gear oil level which is just a hair below halfway with bike vertical. So i'm now beginning to wonder if it is possible for the vent to get clogged, because that gear oil really seems to wants to escape one way or another. I'm not sure the best way to check for this or how it could get clogged, but if this is a known possible issue, kindly chime in.

I can seal around the bolt with something less permanent than the epoxy used above like RTV gasket seal, but want to make sure its not building up more pressure than it is supposed to first..

[docc]

For sure, the vent at the top of the gearbox can get clogged. Most common cause is moisture (kicked up by the rear tire) mixing with the gear-oil making high viscosity mayonnaise (doh - there is no "low viscosity mayonnaise!").

 

Simply unscrew the vent from the gearbox and clean it out with solvent, blow dry.

[4corsa]

Awesome - thanks very much docc! Will report back.