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Howdy all,

This sounds like a familiar problem, but having looked through the threads here, cant really put my finger on the solution.

On arrival in Sydney the other day, decided the old girl needed a bit of a clean...as we do.

Pulled everything off...including as it turns out, the clutch cover. Perhaps a mistake, perhaps not, but squeezed the clutch leaver to check movement of the pads in the basket. Noticed a lovely little pool of blue liquid forming under the bike....clutch fluid was leaking from the left hand side, it appears from the slave cylinder. Removed this to see no sign of fluid so squeezed the leaver again.....no pressure in the system....it had bled dry. Took me a day and a half to repressurise the clutch system again and have positive clutch engagement. Started the bike on the stand, had good plate contact and wheel drive.

Now; came to move the bike this afternoon to give her that wash, started her up, squeezed the clutch to engage first gear.....leaking fluid again...once again, it appears from the slave cylinder. I have looked at the parts manual and think possibly it is part number 93040091A, gasket. Is this actually an "O" ring that fits over the piston in the cylinder?

I seem to remember having a similar problem with my old 900ss, but not sure.

If so, how is the piston removed from the cylinder, cant find that in the workshop manual at this stage...only bleeding the system.

Your thoughts appreciated.

Jaffa

Jaffa, jaffa, Jaffa....

not sure about "outer o-rings" on the slave cylinder...they would only be to keep crap out of the bore...
there was a concertina-type seal on my 900SS...nothing on my 907.

best way to get the piston out is to pump it with the hydraulic fluid from the clutch lever action...it might tap out...but probably difficult with the o-ring contact...

you can usually just "rough" the bore of the slave cylinder to remove axial scratchs.
all you need is about #600 wet and dry on a mandrel.
a cylinder hone will do the trick even better - if you can find one to fit.

don't just throw away the piston seals...most likely they will be OK.
if you wanna lash out on a new set...be my guest...

I dunno exactly what would cause the sudden "major" leak...not by just removing the clutch cover, anyway...usually the seals will weep before totally self-destructing.
if the slave cylinder throw was increased (so the piston was travelling further than normal) the seals may ride up over a "wear-ridge" or scratch in the bore that it normally doesn't travel over??? this could nick the edge of the o-ring seal.

check your clutch rod ends for signs of scoring or damage...it's possible there may be some damage to the throw mechanism that is causing you to push the slave piston further than usual.

in true "Triumph" fashion - you can make an effective bore seal on the outside of the piston from felt; felt seals are good at trapping gunk and you can throw them away and replace a lot cheaper than any Ducati component.

just get some lint out of the back of a clothes dryer filter...pack it in between the bore and the clutch rod.

I just noticed your comment about getting positive engagement back with the clutch.
I'm wondering if the mechanism is "sticky"???
anyway - best of luck with the solution...

Hold the slave firm in one hand, a quick shot of compressed air will release
piston easily into your palm.
Some sanding w wet sanding paper to smooth piston-slave is a good idea.
Clean all w compressed air.
Most likely piston Oring is mushy/shot.

Thanks guys,

All is good. Replaced the slave piston "O" ring. It looked like the original was still in place. This was more a stepped seal than a typical O ring. Anyway, there was a chunk out of it.

Only took me a couple of hourse of pumping this time to re-pressurise the system too.

Expert already......

Jaffa.