I just have to vent. I drove my car around the block twice last weekend. This was a big deal because it hadn't been on the road under it's own power in the 25 years that I've owned it. It has the factory 4-piston brakes that I carefully put back together. Anyway, one of the supposedly SS sleeved calipers let loose and I mean LET LOOSE. Fluid was dripping, almost running actually, from three pistons and from between the two caliper halves.
The car will be down at least a week if not two since these are hard to come by and turn around on rebuilding is slow.
I've told myself that if I can't get this fixed for under $150 I'm going to a more modern set up. I can see why so many people give up on these.
People didn't give up on them; rather, GM did because they are garbage. (The more parts there are, the more things to fail.) Pounds of pressure per square inch is what makes pads bite rotors, not the number of pistions, the reason that the one cylinder caliper has dominated the market.
GM kept them around on the Corvette until 1981. They must not be too terrible.
VBP (vette brakes and products) makes aftermarket pistons and o-rings for the vette calipers which they claim eliminates leaks. They used to advertise for Fbody parts too, and i seem to remember a "big bore" kit from them, but they've gone to concentrating entirely on Corvettes. A call might not hurt though. A complete kit from them for both fronts runs $90 for the vette, so if they can still do the bigger ones, I would hope the price would be similar.
Actually, it's total piston area that provides the extra clamping force. For the four piston calipers it would be total area divided by two but it is still about 15% greater than the area of the single piston design. None of that matters though when they leak like an old faucet.
I opened the leaker this evening and it is SS sleeved - so much for that. I'm going to try a new seal kit tomorrow.
Did I mention that I cannot get my distribution block to seal either? I think one of the seats is bad.
For what I have in this, I could've converted to a Wilwood or Baer system.
I feel your pain. I put rebuild kits in my 4 piston calipers a month ago. Went to bleed the brakes last weekend and the left front caliper pushes brake fluid past the piston boot when the brakes are pumped up.
Well I honed them and put a rebuild kit in and bled the brakes tonight. Hopefully it will hold - I didn't see and dripping at least:) The rebuilt caliper had epoxy almost completely clogging the inlet hole into the caliper bore. There was some epoxy in the hole that transfers fluid to the other piston.
I also had to replace my rebuilt distribution block with an old rusty one because the rear seat (removed for rebuilding) was leaking. I collapsed the seat trying to get it tight enough to seal. Vanco said they would take care of it so we'll see on that.
I also learned that Right Stuff has reproduced the distribution blocks and will soon be reproducing the 2 1/16" 4 piston calipers! That's especially good news because there are no more rebuilt cores available from anyone, anywhere.
I hope to get off work a little early tomorrow and take the car for it's first venture out of the neighborhood.
you might be able to get the dist. block cheaper from piratejack.net
seems like most of the places get a lot of their stuff from mbmbrakeboosters.com (rtstff does), so if you have a business license, you might get a real good deal wholesale.
the dist block is the same as used on some vettes and corvairs, novas./..
Scott: That's a great website! I've bookmarked it for future reference.
I put the seal kit in, replaced the distribution block with an old crusty one, bled the brakes and everything seems okay. That caliper had been sitting for a couple years since it was rebuilt and it looks like a sloppy rebuild (except for the SS sleeves) so maybe that was the problem.
I drove the car a few miles last night! That's the first real drive in this car since I've owned it (almost 26 years).
