Another 348 Slave Cyl Question

Is it oil or break fluid?

You may need to change the o-rings located behind the cover in the back of the bell housing. It's the one in your last picture. There are three of them, one big one and two little ones.

Also did you change the triples seals? If not then do those.

One more thing. Are you sure the leak is coming from the clutch? You may want to have a looksy at the seal, at the front of the box, for the gear selector shaft. That one can get old and leak. There is also an o-ring on the inside of the front tranny cover, but the only way to change the is to pull the tranny. The front seal you can do with the tranny in place though.

 

Change the o-rings on that back cover.

 

Just those four nuts, but you will also need to change the seal too. You can see it around the output shaft. That may be what is leaking?

Maybe you should buy an upgraded slave cylinder from Ricambi, if you are having a hard time getting the old one to seal. Just keep the old one handy as a spare.

But try changing the rear seal first, and o-rings while your at it. They are at least 12 years old. I changed mine when I rebuilt the tranny. It's pretty straight forward. Didn't need to fool with the slave cylinder because it was a new unit.

The only thing about changing the o-rings behind the rear cover is that you are gonna have to rebleed the clutch, and that is a HUGE pain in the ass. But I guess you already know that.

 

interesting...did 4re use the series 1 t/o bearing with your new 1994 car???? I could be wrong but your T/O bearning looks like the one series 1 unit. Later with the USA 93/94 cars for sure the unit had a shiny brushed aluminium looking T/O bearing. You may not be able to use the HILL /Ricambi unit because ferrari also changed the flange. The later 348's upgrade and production of the T/O bearing had an integral flange I think with the blue internal seals. There are pic of it here on FC. Where did you source the black seals for your old style T/O bearing? I need some.
Did you put the seals on the shaft the first time with brake fluid for lubrication? Did you run the T/O bearing up and down the shaft a few times before you put it into action? Also check seals dor directionality. I bet if you put some new seals in there it will not leak. Also check for pits crap on the shaft. Behind the flange nothing pops out just 2 seals for the clutch fluid passages and then a seal like a cam seal that does absolutely nothing. If you are sure it is brake fluid the triple seals are fine.