Leaking output shaft seal

[Bjorn]

My bike tries to keep fighting me for some reason

 

I hope my quantity of technical malfunction topics can go down a bit in the near future 

 

Here goes for the latest chapter:

 

Since i got the bike I noticed the underside of the gearbox was always covered in mud and other sh*t. Never paid to much attention to it. During the building of a exhaust i cleaned the engine/gearbox. After a few testrides i noticed the RH side of the gearbox was ''oily'' again.

 

First i suspected the mating surfaces of the gearbox itself, since the appear to be oiltight by means of liquid gaskets. So i cleaned the box again and powdered it with talcum/baby powder. This revealed the oil was coming from the output-shaft-seal. 

 

Here you see the output seal where the driveshaft connects to the box:

 

And below the best picture i could take of the oil weeping down from the seal:

 

I like wrenching a lot, but im not to happy with this. The timing sucks because spring is already here. I plan on taking the bike on long trips this summer I do want to fix it before I start my holidays. However, i cant imagine im the only one with this seal ''failing'' since the MG shop sells a improved version of this seal. Since im going to fix it anyways, I might as well share my ''adventure'' 

 

I do hope, there is light on the end of this tunnel

 

 

[AndyH]

Bad timing indeed!

Your journeys are invariably informative... :-)

Good luck.

[andy york]

mine has a little dampness too. guess I will tackle that this weekend.

maybe I'll find some voltage down there while I'm at it ... lol

[luhbo]

RPMs at this ring are rather low, so I'd say the risk of a sudden and fatal failure is rather low, too. What if you just watch it another 4 weeks? "Some" years ago it still was a well accepted fact that one or two drops had to be under every hot machine.

 

Hubert

[Bjorn]

I need to order parts first, and the dyno session has to go first as well. I wont risk taking it apart right now. My best guess is that it leaks about 5-8 drops per 100km. Guess i ll be whiping it some more until the fix.

[docc]

If the bike has not run very much while you have been working on it, perhaps a fluid change and some running in will turn it to 3 drops . . .

 

There are many specialized lubricants which may be helpful in this. Not saying it will "fix" the seal, but perhaps give you some riding time before the swingarm must come back off (at least you are very familiar with this tear down!).

 

I wonder if the seal can be exchanged with the gearbox in place. Seal Whisperers will know . . .

[Bjorn]

I am not really a fan of those liquid 'wonder fluids'. Maybe it works without any negative side effects, but they remind my of those tellsell commercials

The seal is mounted in the rear most cover of the gearbox. The manual shows that all the gears and axels are not mounted into this cover. So i need to find a way to get this cover off the bike.

 

In my head: remove swingarm, pork chops, disconnect the engine/gearbox from the rear mountings, remove the clutch master cylinder, try to lift up the rear end of the frame while placing the engine on (wood) blocks. Hopefully this gives me enough clearance to remove the cover. Time will tell.

 

O and the local guzzi shop has an improved viton version of the seal. Gonna try that.

[docc]

Must be a perfect world when your "local Guzzi shop" is Teo Lamers!

[andy york]

Don't take the Cover off ! You will shat all over yourself when everything falls out.

I going to pull the swingarm, remove all driveshaft componets, remove the protective cage,

and see if I can install my new seal. Maybe have to remove the right side porkchop.

Its either that or I will pull the complete tranny off. I'll let ya know later this week

[docc]

 

I'll let ya know later this week

Speaks The Seal Whisperer . . .

[Bjorn]

Sounds like you know what your doing andy! Second time you need to replace this part? Mabye you can take some pictures, combine everything in one topic?

 

Note that i have not done this repair before, however looking at the workshop manual it doesnt look like there are lots of parts housed in the cover.

 

''pulling the gearbox'' sounds scary....

[andy york]

Hi Bjorn,

  You are correct. There really aren't that many pieces to fall out. Its probably a coin toss as to which is 

easier. BUT.  I can probably rebuild the motor without taking it out of the frame, But I'm NOT.  

Just hate to see ya open it up to the environment thats all. specially if we can do it without taking the cover off.

Even if I pulled the tranny  I would not pull that cover off unless there is another issue.

[Bjorn]

Looking forward to your findings and pictures andy!

 

But how would you replace the seal without getting the cover off...? pull it out with parker screws or something?

[andy york]

Well,  everyone will have to wait a little longer. I may have determined that it is not leaking. It appears that I may have a little blowby from the tranny vent. I will take a few longer day trips and see what happens.

My question back to you Bjorn is " If you could not pull the cover, how would you get it out"?

anyway    thats what old busted screwdrivers are for.  Heat, grind, bend till you get it in the shape you need for the project at hand.

And be very carefull prying it out----don't want to scratch or gouge the shaft .  It is dooable tho

[Guzzi2Go]

I developed the same problem when riding my Mille GT back from Sweden to Germany back in 2006 (or so). A small leak I noticed first tank stop after Stockholm grew into serious leak by the time I reached Copenhagen, rear tire being completely drenched by then, luckily only the sidewall. Had to buy a can of oil and top up every tank stop till Düsseldorf. These things can go quick. 

 

Fix was easy. 2€ + sixpence for the seal, swingarm down & out, fishhooked the old seal out, punched a new one in using a plastic canister cap.

 

Piece of pie!