Help with 355F1 throwout bearing

Where the 348 and 355 manual cars have an easily-accessible 2-bolt plate which secures the throwout bearing to the flange, the F1 cars have three 13mm studs which provide more precise in-and-out movement of the throwout. The remaining two studs are on the passenger side of the throwout and cannot be seen in the picture below.

Each stud (part 166595) offers only inches of clearance until the entire flange/bearing is removed from the clutch pumpkin as a single unit where standard length wrenches can be used. The heads of the studs also have very little height to properly grip a wrench (even a flare nut wrench) and therefore round-off easily. Further I suspect the studs are reverse-threaded.

I cannot locate even a basic list of steps for the F1 throwout replacement. The manual transmission throwout swap is cake compared to this thing. Anyone ever replaced the F1 throwout bearing (Hill part CRB355F1S or the factory part 170182) and can offer any tips? Thanks.
Ken
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The throwout bearing cannot be removed from the shaft until after the end of stroke studs are removed first. Also, a socket is blocked by the mounting ears on the throwout. Because of this, the only way to remove the studs is with an open ended wrench.

I just saw that Hill makes replacement studs with the description:

"Made from much stronger material - original item made from very low tensile steel thus rounding of the hexagon is inevitable."

166595 - 166595 Stud by: Hill Engineering - Hill Engineering Ferrari

I suspect shops like Bradan either cut and replace the studs or have some type of vice and flare nut wrench specifically designed for this very problem where the nuts get rounded off.

 

Actually that was the only way to get significant leverage on the studs so I removed the flange and throwout together. While the assembly is off, the ATF fluid from the F1 reservoir leaks continuously so it needs to be a quick job.

With the studs frozen to the flange, I think they need to be cut from the post, the throwout removed and the lower stud half (still connected to the flange) can then be taken off with a simple socket.

I keep hoping there is another way and I plan to try heating the stud with a torch but the bottom line is the studs will likely need to be replaced.

Again, I suspect the authorized repair shops always replace them anyway. More specialized shops like Bradan may have fashioned tooling to reuse the studs but they have quite a headstart on us.

I keep hoping there is another way that I am overlooking.

 

i think you are probably right, I am planning to try heat next. Is it better to heat the flange or the stud?

 

This is precisely what I did. The bolts came out easily once the throwout was out of the way. Had I seen this post from a few years ago I would have been prepared with the 3 new end of stroke studs as soon as I went in:

http://www.ferrarichat.com/forum/142594455-post1.html

As it is now, I am waiting for Ricambi to open back up on Monday and I can hopefully complete the job Tuesday after work.