Just replace the whole wheel cylinder. It's just as cheap and easier than rebuilding them.
How do you get the brake piston to retreat back in caliper ?
You will need special brake caliper tool such as a C-clamp to push back the piston on the caliper of a 2002 Mitsubishi Lancer.
You can adjust the brake pistons by adjusting the brake piston adjustment screw. Turn the screw to the right in order to back off the brake piston.
There is a 14 mm bolt on back of caliper. Remove this & use a 4 mm Allen wrench to back piston into caliper.
Yes. Brake caliper compression tool. Ratcheting calipers
Where did it go? hahahahahah, gosh your funny!...and now for a helpful answer. when you were replaceig the pads you would have pushed back the piston in the brake calaper. Once you have put everything back together you will need to pump the brake pedal a few times to push the brake piston back out until the bad is snug with the disc. check the brake fluid level also as pushing the piston back will naturally force the brake fluid back into the reisvour. Make sure the fluid didn't oveflow and spill over the engine bay. If your still having issues get a qualified mechanic to look over your work.
The rear disc break pistons on Mazda are not to be pushed in. Instead you turn them in clockwise.
If the piston is just a solid or hollow cylinder, you can use a pair of big channel locks and an old brake pad to squeeze it back in, if the piston has little cut outs in it you will need to rent a tool that twists the piston back in to place, like a bolt.
If you can't compress the piston with a C clamp back in to position to fit the new brake pads I would suggest replacing the caliper completely.
take the old brake pad and put it back in the caliper and then take a vice big enough to get around the caliper and the inner piston. just press on the vice and it will return, do this till it stops. if it becomes difficult you may need to lubercate the piston and also open the brake reservoir to re leave the pressure. well I hope that helps
Remove the wheel, and brake assembly (4 bolts on back of calipers) be sure to hang the brake piston so that it does not hang by the brake line, remove the rotor, clean and inspect all parts including brake pads. Open the brake fluid resivoir, get a c-clamp or a piston depressor to push the brake piston back in. This should take about 15 seconds to SLOWLY push the piston in. Re-assemble brakes and repeat on other side.
The back brakes on my Honda Accord are disc brakes. After removing the brake cylinder assembly you will see the brake cylinder piston end has a slot in it. The short pin on the back side of the inner brake pad fits into this slot, but also it is used to 'Turn' (clock-wise) the piston back into the cylinder so you fit the assembly back over the new 'thicker' pads. You can not 'press' this piston back into the cylinder.