Caliper cleanup & rebuild *pics*
 

Since I was unable to find any caliper rebuild how-to's with images, I thought I'd snap some pics of mine as I went, maybe share some insights along the way. Here are a couple "before" pics.

The caliper really is not as dirty as it looks. A summer of track days turned my cheap caliper paint dark / black. This was the Dupli-Color caliper paint - only rated to 500 degrees.

You can also see the calipers were in dire need of attention. Note the cracked dust boots etc.

Here's how I went about removing the pistons. Ensure you have something to stop the pistons or they will fire out with surprising force and spray brake fluid everywhere. (Voice of experience...)

Here is a before and after of the pistons. It really took some work to get them back in shape. They were scarred from being forced unevenly into their bores, but fortunately the scarring came out with some red jeweler's polish. Before that I cleaned them with steel wool. Do NOT use sandpaper or anything abrasive that might scratch the mirror finish on the pistons!

Oh, and if you need an excuse to purchase a Dremel, this would be a good one!

I definitely needed to clean up the calipers before putting any new paint on them... nothing else would even begin to remove it, so I had to use the intense stuff...

then lots more use of the Dremel to get it to this stage...

This pic doesn't really fit here in the flow of the project, but at some point you need to remove the old seals. The "dental pick" tools are invaluable for this.

After you get these out, clean the bores, then clean them some more, then clean them some more. Get absolutely every little bit of dust and grime and grit out before inserting fresh seals.

Use only brake cleaner for cleaning, as any other cleaner can leave a residue.
And use only brake fluid to lube the seals for reassembly!

The seals and fresh dust boots come in a "caliper rebuild kit", available from Mazdatrix.

I'm missing a pic of the completed caliper with boots replaced... it was blurry. Sorry. Safe to say it looked much better than the "before" pic in the first post.

Anyway, several coats of Plasti-kote 1200 degree caliper paint later, and with some Dremel sanding and polishing of the Mazda logo...

I'll add a final pic with the wheels on in a few weeks when I get some shiny new rotors and am able to get the car out and give it a cleaning...

Now, did you just use regular old brakekleen for this type of work, or did you use anything special for cleaning out the dirt in the caliper piston holes?

I used regular old brake cleaner. Absolutely nothing else should go in the caliper bores. I'll go back and edit that post, cuz that is important. Clean with brake cleaner only, ensure it is all evaporated before reassembling, and lube only with brake fluid during reassembly.

impressive work
what kind of pads rotors and fluid are you going to use and do you have ss lines?

I wish I could say I had a pad and rotor I'm happy with, but I can't. On the street I'm fine with whatever rotor and Axxis Ultimate pads. For track days, I'm still looking for a pad that lasts longer than a weekend and a rotor that won't warp in a weekend. Suggestions welcome. I am installing the N-Tech backing plates and 3" ducts which should help significantly with this next summer. As far as fluid goes, I use Motul 600 for the track - and yes, I have Goodridge stainless lines.

I use the ATE Super Blue in my audi with Porsche Boxster Calipers. Now, I couldn't tell you how much improvement that made, as I made the switch when I put the new calipers on, but I havn't had any issues when the brakes are hot.

nice work! thanks for the "how to" :).

great write up and nice pics....should serve to help many of us in future brake rebuilds. THanks
RYan

Cool, thanks.

Nice writeup! The caliper looks awesome all new and shiny :). You did a great job cleaning the pistons up - I'm amazed at the shine you got! :)

I've rebuilt my FC calipers a jillion years ago - it's actually pretty easy. Just be sure to use the right stuff for cleaning everything (brake cleaner and brake fluid for lube) and it's all good.

Dale

looks dope

oo for u guysthat wants to paint your calipers dont use the duplicolor brand

that u have to brush it on instead of spray

it sux a$$, i got another pait from auto zone and looks clean!!!

i will start my own thread later with pics

nice work btw

mike

Great post. People always wonder how the pistons come out and the rebuild kit is very cheap!

Did you paint the entire caliper or just the exposed side? And also, has anyone tried to rebuild the rear calipers? I want to paint my rear ones too.

Rears are probably due also, but fronts were my big priority.

I masked off most of the back and mounting points. No need to waste paint or have the mess in threads or on mounting points...

Very nice indeed. Great thread.

just curious do the piston seals have direction?

I noticed that the seals have a red and green line on them, I wouldn't know how but are they supposed to go in a certain way?


thanks
Rip

Great timing!! I was just about to remove my front calipers to do the same thing!! I just got online to do a search on a how-to for this project, and it showed up right in front of the 3rd gen forum. Thanks for the info. :D

bump

So Zullo, how much to send you my calipers and you give them your treatment in black with a polished mazda logo?

-Joseph

wow those came out really nice, good work

Too much ;) While straightforward stuff, the work is fairly tedious. Track season is upon us and I'm not going to have a lot of time for extra projects while fixing the stuff I'm bound to break...

Thanks for the compliment tho! :)

Great write up, thanks. I don't suppose there is anyway to get the pistons out without using compressed air? I just got my rebuild kits for both front and rear calipers, but I don't have an air compressor.

its pretty tough. you can remove the caliper and pump the brakes. since there is nothing for the pistons to press against they will pop out. problem is its likely only one will pop out and thats the end of that game. you can try fiddling with blocks of wood and stuff to try and get each out enough to pull them the rest of the way. i took mine to a shop and got them to do it. it was a mazda dealer actually and they did it for free.

Very nice job!

You can use a bicycle pump if you have something to seal the hole for the brake line and an attachment for the bleeder valve.

https://www.rx7club.com/suspension-wheels-tires-brakes-20/brake-caliper-piston-removal-333883/

;)

I need to do this very soon, thanks for the writeup. I am debating powdercoating vs painting.....

Thanks Mahjik, I limited my search to the 3rd gen forum like a dolt :o

Thanks, I may try this since amazingly i have a bicycle pump despite the 2 bikes that haven't moved in 5 years.

I just rebuilt my fronts this morning.

A couple of extra notes:

1) take care to be sure the dust seal snap rings are fully seated. The groove they snap into isn't very deep and one ring I put in was almost but not really seated.

2) I had no compressed air. I removed the pads and pumped the brake to compress the pistons onto the rotor. This extended the pistons about 75%. Watch your brake fluid reservoir here, since you'll be pushing a lot of fluid into the caliper.

When removing the pistons, I was able to pull two of them out with my fingers. I used a channellock pliers to grab the other two holding them on the part of the piston that sits outside the dust seal groove. I gently rotated the piston back and forth while applying pressure to the channellocks to pull out the piston. Do NOT touch good part of the piston.

3) Push the pistons 100% of the way in before installing the caliper.

Also, next time you're changing pads, make sure the pistons are sufficiently retracted into the caliper. Otherwise you'll shred your dust seals and have to rebuild them all again.

Late Question
 

Please excuse my reviving this old thread, but can anyone tell me whether the MityVac can provide enough pressure (about 18 psi) to extend the pistons of the front calipers?

mity vac=no

OK, thanks. I'll use my tire air compressor, then.

i have a question, when you take off the caliper, does the brake fluid just start rushing out or anything, or does it stay in the line? i want to clean and repaint mine but dont want to mess anything up

i am rebuilding mine right now. The fluid just dripped out, no gushing. I would get a cup or something to catch the fluid in though.

Only one piston came out on one caliper using air pressue and 2 came out on the other. THe board I used was too small and let the piston come all the way out. I haven't had time to work on getting the others out.

Quick question though - can you use degreaser to clean the outside or only brake cleaner?

That looks awesome!

If you are having issues keeping your rotors from warping you might want to look into cryo... I've heard you can't warp a cryoed rotor.

I am currently rebuilding my calipers also. I have been looking for a metal polish to do this. Anyone have any recommendations? I have checked with a lot of local auto stores and mostly get blank looks when I tell them what I need it for.

Hardware store.

when i got my caliper rebuild kit, it came with red grease specifically for the piston seals - should i use it or use brake fluid only to grease the piston chamber?

I have a question here

I have a small and a big air compressor,. small one for pumping tires, Big one for air tools (oiled)

Will this tool work with my tire compressor ?

http://www.sears.com/shc/s/p_10153_1...ol+Accessories

or This ?

http://www.sears.com/shc/s/p_10153_1...ol+Accessories

Thanks

Thanks for taking the time to share!
 

Great job and nice pics along the way.

Enjoy the summer!

I don't know what kind of compressor you have. I pressurized mine with my 5 gallon compressor. Two of the four pistons came loose. I had a heck of a time trying to loosen the others. I decided to take it "Just Brakes" They popped them loose at no charge, degreased the caliper and gave me a small bottle of assembly lube. I think the guy running the shop was impressed it was for an RX7 or he was going to charge about 20 bucks. 20 bucks would have been worth it any way.

So, with my experiance - try your compressor at home (with a piece of wood between the pistons) and if that doesn't work - take them to a brake shop where the have the tools to help get them out.

Looks really clean now.
Take some pics with them on.

So, those are the right accessories ? right ?

Hmm, my compressor should be able to, its 10 gallon with I forgot what 3 or 5 hp ?

Thanks a lot sir :)