skpyle

Hello Gentlemen and Ladies...

I want to beat a dead horse because I am late to the party. My 1986.5 S3 Red Witch has the early Brembo calipers with the 42/36mm front and 30/28mm rear pistons. Being early, they have the scraper type dust seals.
As far as I can tell, I am SOL on the front 42mm scraper dust seals.
I have searched 'Brembo' on Rennlist 928, and found some good info. Such as Centric reseal kits can still be found for front and rear. However, for the fronts, it is only for the early 44mm pistons.
I have searched the internet to no avail for 42mm scraper dust seals. I have found 42mm pressure seals, but no scrapers.


So...here are my options as I see them:
-get a set of later S4 Brembos with the commonly available dust boots, rebuild them
-suck it up and run my calipers as is
-get the Centric front and rear early seal kits, use the 36, 30, and 28mm seals and scrapers. Get Centric generic 42mm seal kits with the dust boots, use the 42mm pressure seals, discard the dust boots and hope like h*ll my original 42mm scraper dust seals are still worth a darn


Here is my reasoning for poking this dragon with a stick: I have spent untold hours and dollars chasing my dream on my 928. I have gone through/will go through just about every major system on her. None of the pistons leaked on the car when I drove it and took it apart. However, they have been off the car and in storage for over 3 years. I R&R'd the caliper spring plates to soda blast the corrosion followed by paint. I replaced the spring plate mounting hardware and installed new Brembo bleeder screws. However, I did nothing to the pistons and seals. I THINK they will work just fine. However, I am afraid I am going to start driving the car and they will leak.
I have a new master cylinder, new brake booster, 33-bar residual valve, and new braided steel flexible lines. I have replaced the metal brake lines from the Tee junction block at the back. I will likely replace the metal brake lines to the calipers at the front. Having done all that, I think I should address the caliper pistons and seals.


Anybody have any new information on these early scraper seals?
Am I on the right track with my thinking?


Thank you for your time and advice.

linderpat

Seth, you'll hate me tonight, and (hopefully ) buy me a beer in September - but here's my advice - STEP AWAY FROM THE CAR - TAKE A DEEP BREATH - and put them back on (you said they weren't broke) and just use them!

This car is begging to be re-assembled, and we all want to see it, hear it and enjoy watching you experience it.



Otherwise, any of your 3 options will work

jcorenman

What he said ^^^

Rule #1: If it's broke, fix it.

Rule #2: If it's not broke, then fix it until it is. Then see rule #1.

skpyle

You know what...I can live with that.
I was just afraid of ‘Doing Something Stupid.’

Thanks, gentlemen.

Ed, of course I will buy you a beer!

hacker-pschorr

3rd vote to bolt them on and run'em. You know the history. If these came off a random parts car that might be a different story.

You have a power bleeder? I'd invest my time / money in one of those, once everything is together and filled up with fluid, leave the power bleeder on as you go around checking for leaks.
Easy Peasy Lemon Squeezy.

This isn't a part that is buried under more work if you find one leaking after the fact. That's my criteria for such decisions, how much "extra" work will it be to pull it back off. Calipers are easy.

Adamant1971

Have you looked at paragon?

That's where I have been getting my rebuild parts.

https://www.paragon-products.com/Bre...kits-early.htm

ROG100

I stock all the seal kits -----
Caliper Repair Kit - Dust Boots & Pressure Seals - 86.5 to 88 - Front 36mm & 42mm - $36
Caliper Repair Kit - Dust Boots & Pressure Seals - 89 to 95 - Front 36mm & 44mm - $36
Caliper Repair Kit - Dust Boots & Pressure Seals - 86.5 to 95 - Rear 28mm & 30mm - $25

Tomkat80222

What, you didn't call Roger first!

skpyle

Thanks, hacker. I thought about that last night at work. If the calipers go south, it is not that much effort to take them off. You are correct, I have experience with these calipers, and they did not leak.
I most assuredly have a Motive Power Bleeder. Been using it on brakes for years. Very good idea to pressure test and check for leaks. Thanks!




Thanks, Adam. I have looked at Paragon, but it only seemed like they had piston/seal kits. A little spendy for what I want to do right now. Thanks, though.




Well, h*ll! Roger, I did not know you stocked the seal kits. I am assuming these are for the early calipers with the scraper dust seals? If so, I will be getting seal kits from you. Reverse Murphy's Law. If I have them, I won't need them...




No...I kinda screwed that up. Last post I read about early Brembo seals (from 2017), Roger said he only had the piston kits. I don't need pistons(I think...), so those kits are way spendy for what I want.
However, now that I know, I will be sourcing them from Roger.



Alright guys, I have a plan: calipers are going back on just as they are. If there are issues, I will deal with them.

Thanks!

Adamant1971

Go with Eric’s advice and just run them. Rebuilding them is a PITA

skpyle

That is very good advice. That I will be taking.

karl ruiter

Your best path is to not do this. But if you do decide to, hit me up with a PM. When I did my S4 I ordered the wrong size parts, which are probably correct for your car and have them sitting around somewhere. If they are correct, you can have them for free. By the way, I did my S4, not because of seal degradation, but because the pistons can become pitted and start to stick. So I was replacing the pistons and did the seals at the same time.

skpyle

Thanks for the offer and advice, Karl!
PM sent.

OJ GTS

Brake engineer here, assuming the pistons are in superficially good condition and if you correctly masked off the calipers when you blasted and painted them so as to not expose the piston seal area to any contamination, then just send it

if there’s ANY risk you’ve contaminated the seals, then change them. To give you an example we had a Nissan GTR in recently with very strange pedal feel problems and it turned out to be where our distributor had blasted and painted the calipers without following our instructions. Instantly cured by new seals.

Any 42mm generic wiper seal will be fine, the pressure seals are the important bit.

Have a look for an Alcon reseal kit for a caliper with the same diameter pistons if you’re struggling, we still use wiper seals.

skpyle

Hello OJ GTS,

Thanks for the advice! I heavily masked off the pistons in all the calipers with duct tape before I blasted the corrosion with baking soda. I remasked them again with blue painter's tape when I painted the corroded areas in the calipers. The wiper seals still look good.
I am going to reinstall the calipers as is and just send it.

Thanks!