caliper rebuild???

[911tracker85]

refreshing an 86 944 Turbo to be my DE track car.

although they did not look too bad, wanted to rebuild the calipers.

I quickly found these rebuild kits are no longer available through Porsche.

searched this forum and found a few threads that referenced sources. ordered a set of rebuild kits from one of them.

well.... the specs for the piston size were correct so pried out the rings from the old/destroyed dust boot, pulled the seal, and cleaned them up.

the new seals went in perfect. but the dust boots would not fit. for example, on the dust boots labeled 38mm, the OD of the dust boot was 48mm but the opening on the caliper was only 46mm. same on all the pistons. talked to the supplier and the explained these were 'generic' kits based on piston size.

has anyone found a source for these that fit?

[kachunk]

Racers Edge should be able to support. I used them when I rebuilt my calipers a few yrs ago.

[911tracker85]

thanks for the info ... for the next time.

what I learned is these calipers have scraper rings and not the dust boot I am used to.

found the ones still available.

[Grandad#3]

Where did you find the correct rebuild kit for the 86 brembo front calipers?

Cheers,
Larry

[911tracker85]

when I started to rebuild them, one contact told me these kits are no available from Porsche.

when I was searching threads, found a reference to StopTech. I knew about them but had never ordered anything. contacted them and they said they had kits for these calipers. ordered and found they matched the piston sizes but had dust boots, not the older scraper rings.

out of ignorance, I had initially thought all the dust boots had disintegrated. was not aware of these scraper rings. I had already pried the scraper rings out of one caliper, damaging a couple. up to now, all calipers I had rebuilt used dust boots.

since these caliper/pistons were not made for dust boots, they would not fit. the metal retaining ring on the dust boots is about 2mm larger in diameter than the machined space for the scraper rings.

I found that a couple of the correct scraper rings are available, but not all. what I got was from Paragon Products as I found them on their web site. I suspect PP may have them, but did not find on their web site at the time.

so ...

IIRC all that remains is the 38mm and 30mm, and the 36mm and 28mm are no longer available.

after some improvising, I was able to cut a very small section of the metal ring on the dust boot so it would compress into the space for the scraper ring.

well.... since not made for dust boots, not enough space for the dust boot to fold down flush and it kept popping off the piston when compressed into the caliper.

after more contemplation, turned the dust boots upside down, and then trimmed all the excess 'boot' material so what was left is the metal ring and just enough of the old dust boot to act as a seal to prevent debris getting down and causing damage to the internal seals.

destroyed a few dust boots getting this to work, as cutting the metal ring can lead to the rubber boot material tearing too much to be useful.

once I learned all this and began on the other calipers, did replace all the inner seals but retained the scraper rings as they were actually in good shape.

good luck, but it appears we are limited in this area by what is available. if what you need is just the internal seals, the ones from StopTech worked fine.

[Grandad#3]

Thank you for the much needed information on the caliper rebuild.

Cheers,
Larry