Phokaioglaukos

Last time I changed my brake pads one of the ceramic (?) discs attached to the one of the pistons came off. This is not the anti-squeal disc/spider, but was attached to the center of the piston through a depression with a hole in the middle. I put it back in place with the new pads, but of course it is no longer attached to the piston. I surmise that the function of this part is to reduce heat transfer from the brake pad backing plate to the brake piston/caliper/fluid by providing some insulation.

Is there a proper way to reattach this disc or can it be replaced? Do I need to replace the piston, too?

I sent this to Joel Reiser, who replied:

I think what you are looking for is what Porsche calls "Repair kit, protection caps", you need 3 sizes... 996.351.915.01 38mm, 996.351.915.00 32mm, and 996.351.917.00 28mm. You would order two of each (1 kit should do 1 caliper). There is also a repair kit with the caliper hardware... 996.351.959.30. It looks like you would just order 1, but I can't tell for sure.

fhp911

YES! This happened to me also. It was barely fastened, and it fell right off the piston when the new brake pad slid by it.

I kind of squeezed this 'cap' back into place and hoped for the best when I installed the replacement pad.

-> How do you install the 'protection caps' as Joel Reiser calls them so they stay in place?

g3tcs

I bought some 6 pots to upgrade my Mk1 brakes and noticed when refurbishing them that the ceramic discs are held in place with a smear of clear silicone sealant.

I sourced some high temperature silicone and stuck them back in and although the temp resistance of the sealant was only 300 degC they are still in place.