chenishead

I was working on my brakes with a buddy and he did not have the pads in the front caliper while I pressurized the bleeder. The pistons in the caliper extended out and now they wont go back in. Help somebody! How do I fix this? I was so close to finishing...

Anyone know what comes in the dealer overhaul kit? I searched some but did not find anything definite. How would I go about replacing the seal and boot on the calipers, both front and rear?

Sorry for the bad quality, was a quick phone pic...
<img src="http://i180.photobucket.com/albums/x125/chenishead/Untitled-3.jpg" border="0" alt="Photobucket">

mAgnum8

Did you try a C clamp?

chenishead

rubber mallet and it did not even budge. This seriously sucks...

j-manic

I have to turn the piston (clockwise I believe) while putting pressure on it with a C-clamp. They said I would need tool, but it wasn't necessary. I don' know if the two piston is the same, maybe someone else knows.

Kneale Brownson

Re: That should apply to a rear brake caliper. Fronts should go straight in

TwoTonic

Here's a photo and link from the Brakes Section. Looks like there may be a Harbor Freight tool that helps a lot.

Good luck!<ul><li><a href="https://forums.audiworld.com/brakes/msgs/1642.phtml">Brake Piston Clamping</a></li></ul>

PsYcHe UK

Have you taken the top off the brake fluid reservoir? Or tried undoing the bleed nipple while compressing?

Had a stuck piston on the wife's car years ago and had to take it out then sand with some emery paper, then pop it back in (worked great after that), but we did have to take the lid off the reservoir to get it back in.

Kneale Brownson

I'd remove the caliper from the car and work on it on a bench. You'll have a tough time getting the pistons aligned and restarted straight while on the car.

A dealer (or any other parts supplier) overhaul kit should include a new seal for the cylinder and a new boot for the piston. For this caliper, it should include two of each.

I don't know what a "correct procedure" for installing pistons back into calipers is, but mine is to get the seal in place, well lubed, I stretch the boot over the base of the piston, lightly lubed, insert the boot into the cylinder, square up the piston with the seal and press it in, usually by hand. I've occasionally had to use a C-clamp to get it started in. Having the caliper in a vise makes it all doable.

gondar

they went out past the sealing rings and the rings moved into the bores and are hitting the piston bottoms, blocking retraction.

audikillsbmw

If it isn't lined up just right, it won't go in.