went to change my font brake pads today and pull the driver side off and was depressing the pistons but wouldnt you know one of my pistons wont depress... is my best option here to just rebuild it ?

 

you can rebuild it if you like.

If I remember right, convertibles have 4 piston calipers. Last year, I bought a new 4 piston caliper for my gxl for $50 with core change (forgot how much the core was and this was with my friends emploryee discount). I bought it from NAPA

Also, are none of the pistons moving?
rebuild kit from mazdatrix is around $35

 

Remove the pistons and check the condition of them and the bores. If either any significant pitting present, go for a reman. Otherwise, clean up the bores and pistons and install a rebuild kit. Recommend you do both front calipers at least. Would be smart to do all 4 while you're at it.

 

If the piston(s) won't move in, open the bleeder and give it a try. If the pistons still don't move in, they're stuck, but if they move in, internal break in flexible line.

 

good advice on the hose.

 

Got my money yet (after a whole year)????

 

3 / 4 pistons depress the top back piston is 1/4 way out and wont budge the other 3 went in depressing them when i open the bleeder .. ordered a rebuild kit today ..

 

Hi,
I replaced my brake pads yesterday, and I had to really crank down on the C clamp to get 3 of the caliper pistons to retract, but They finally did. I noticed that as they began to 'give', they would rotate with the clamp as I turned it.
My question is - does that mean they are "unseized" now (yay?), or do I still have a problem? Should I replace them now? Rear calipers seem to be scarce as hens' teeth. Not surprising for the age of the car. I'm probably not inclined or capable of rebuilding them.

 

You did the process wrong. You don't just press in the rear caliper pistons. The piston is rotated clockwise to get it to retract.

 

Yeah, the rear pistons are supposed to be rotated in / out with a special tool that grabs the two divots on top of the piston and rotates it. The piston threads down on this central screw thing.

They probably weren't seized in the first place.

I would be extra careful on the next few drives until you know everything is working okay. It's probably fine unless you felt anything snap when cranking down the c-clamp, but you can't be too careful.

 

Oooooooohhhh! Well, they did start rotating clockwise, as the C-clamp was turning clockwise. And I didn't hear anything break. Fingers crossed on this!
Special tool, but only on the rear ones? Why did they do that? The front is just a hollow cup that is pressed in. ... right?
Glad I replaced the emergency brake cable too...

 

The rear piston is screwed in because of the parking brake. As the pads wear it allows it to get closer and take up the slack.
Modern cars have separate drum brake inside the rotor for parking.

 

JTSO, thanks for the diagram. Always good to know what I've gotten myself into.
Oddly, my rotors have the "drum" shape for separate E-brake shoes. I may have installed the wrong rotors in the past...?
These calipers are ones that came with a rear wheel/differential assembly I bought used out of OK years ago (always good to have a spare differential?), so when I did my last brake shoe replacement, I thought those calipers were seized too. So I just swapped out calipers and shoes etc. at the time. I held onto those old calipers,stuck paper towel into the brake line opening and stored them in my basement. I guess its time to rent the tool to see if those pistons will rotate back in. If so, I'll buy the rubber parts replacement kit for the slides.
Boy, do I make projects for myself!