GregBBRD

"Rebuilt" discs, regardless of who rebuilds them (Spec uses rebuilt discs) all come with the same potential issue. While the clutch material is replaced, the splines that the clutch short shaft go through are used....and frequently abused.

Because of a general lack of knowledge/ability, these splines are rarely properly lubricated and come out extremely rusty and worn from the lack of lubricant.

"Rebuilders" pay little/no attention to these splines and wear can make the discs "hang up" on the clutch shaft, further adding to the mystery/misery or a "new" clutch not releasing properly.

The other issue with rebuilt discs is that the replacement lining is frequently too thick, leaving the pressure plate with extremely limited travel, in order to release.

Remember, when doing work yourself, you become the final quality control manager. A little bit of knowledge is dangerous...and getting a lot of knowledge is almost impossible, when doing one or two clutches in your lifetime.

Study up. Look closely at the pieces when it comes apart. Look closely at the pieces you use to re-assemble.

I use specific pieces, for specific reasons:
In my world, time is money....and at current shop rates, redoing a clutch job because it doesn't work properly is costly. And if a client insists on me using "inferior" pieces, that "second" (or third) clutch removal and installation is on their dime.

New stock clutch discs get to look really cheap, really fast, for me.

Carl Fausett

I didn't see the intermediate plate mentioned as a source of his possible chatter. Of course, if it has blueing and hot spots, it will cause a chatter just like a flywheel will.

Next thing might be which friction disks and pressure plate was installed when you did it last time. Were those stock parts? Or aftermarket performance upgrades? Because the performance clutches are designed to hold higher torque loads, they are designed to be more grabby. Because they are designed to be more grabby, you need to use more RPM's during your shifts when you blip the engine as you let the clutch out. Then they will not chatter. Use too low of rpm's, and you will induce the chatter.

Please let me know ho I can help you.

yoni_d

Thanks Greg! I had no idea that SPEC uses rebuilt discs. I wonder if 928intl after market uses also rebuilt discs.

Carl, when I renewed my clutch parts some years ago I had no idea what to look at. Therefore, I do not know what was installed. I do know that the discs were re-covered and every part was balanced (at least that what I was told).
I am pretty sure that the discs are not performance discs and there were regular stock discs.
Since I am not sure the parts I have, the condition of the parts, I prefer to start with a clean page. Choose the correct clutch with relevant parts and if the shattering continues - I will at least know where to go from there (maybe...)

yoni_d

Guys, I have another question. About 7 years ago when I have rebuilt the clutch I also replaced the T/O bearing (but not the guide tube). In those 7 years the car did maybe 35K km. Which is nothing. Since I am going to replace the clutch soon, I thought (among other parts) to put a new T/O bearing + new guide tube.
Do you think I can re-use my current T/O bearing and guide tube or just replace it to be on the safe side? I know it is recommended to replace it but since I haven't drove the car much maybe I can skip it?

GregBBRD

Again, you need to take the entire clutch out and inspect it.
Replace what is bad...reuse the rest.

yoni_d

Thanks Greg!