Log in

View Full Version : Time for new calipers?



winningblue
01-01-2014, 04:24 PM
I've been slowing restoring my recently purchased 1991 NA and decided I would rebuild the calipers. I started sand blasting one of the rears today and got it looking pretty decent:

http://i.imgur.com/gAvOFjO.jpg

But on the back side I noticed something that worries me:

http://i.imgur.com/gVtbMuM.jpg

It appears that at some point in the past somebody installed rotors of too large of a diameter and it rubbed on the caliper, all the way through the metal and into the guide pin hole. I've checked the other rear caliper and the same thing has happened to it too, no idea about the fronts though as I haven't gotten them off of the car yet.

So what do you think? Time for some re-manufactured calipers or do you think these are still safe to use?

winningblue
01-01-2014, 06:43 PM
Looks like I just need to replace the brake bracket. Replacement part number Cardone 14-1025 if anyone is interested. Mods, feel free to close.

WASABI
01-01-2014, 07:52 PM
Hi winningblue, brakes are pretty important to the safety of your car, and should be done correctly. While the front brakes of the Miata are pretty simple, the rear brakes are a whole different animal, with hidden adjustment screws, sliders, that need yearly greasing, and parking brake integration.

First thing's first, I wouldn't sandblast the whole brake caliper all together. You really should disassemble it and rebuild it, if that's you end goal. The main reason I see is that you are forcing sand/grit into places that it should be, such as the slider pins, or brake pads. It would be easier to buy a set from an auto parts store for around $75.00 each, and paint them before you install if that's your goal.

Good luck,

Jim

winningblue
01-01-2014, 08:21 PM
Thanks Wasabi, I realize now that I got a little trigger happy sandblasting before dissasembly like I did with the one caliper. I do plan on tearing apart the other before blasting and doing a full rebuild with new seals all around for everything. I can agree grit getting places it shouldn't be as I've already found some after removing the piston. I'll do a full cleaning and lube of everything and if I don't think I've done it right I'll buy refurbs. I'm doing all of this as a learning experience but in the end I'd rather be alive than experienced.

kung fu jesus
01-01-2014, 09:54 PM
Disassemble and tank the calipers.

http://mazdaroadster.net/showthread.php?t=1859

WASABI
01-01-2014, 10:02 PM
I'm doing all of this as a learning experience but in the end I'd rather be alive than experienced.

Having rebuilt the brakes twice myself, I can tell you that it's not difficult, but it is involved as far as the rear brakes go. AND, I recently disassembled a set that I rebuilt about 5 years ago, and found some corrosion around the piston. I'm not sure if it was something I caused, as in not seating the rubber boot correctly, or something that happens with age when a car gets driven year round in New England. But, there was so much corrosion, that I ended up buying a rebuilt set.