Per my post yesterday, I was replacing the rear pads and rotors.

I just screwed one of the rear caliper pistons in clockwise, but I didn't know how far. I guess just enough to flatten it against the housing. I noticed a minute amount of brake fluid in between the seal of the piston and the rubber boot around it. Should I be concerned? Are you supposed to turn the piston clockwise until it flattens against the housing? The piston turned easily, but I should have considered that I might be grinding the seal against the cylinder if I kept on turning clockwise too much????

 

Hmmm, I'm pretty sure that there should be no fluid between the seal and the rubber boot. I typically only turn caliper pistons enough distance needed to clear the pads and re-mount the caliper. Uhh, I'd keep an eye on it, and watch out for a leak down the road. You'll be able to tell if it's leaking significantly as the reservoir fluid will go lower, the brakes will be a little harder to stop, and most times leaking fluid appears on the rear tire when the caliper leaks really badly.

 

That's how I do it. The seal is probably just bad, but it probably won't leak with the piston back out.

 

I'm putting in new rotors and new pads, so I need maximum clearance.

I have the lifetime warranty on the calipers at autozone, but don't want to have to go through the trouble of disconnecting the hydraulics and getting the new parts etc. etc.

I probably should have replaced the calipers though while I was at it.

The fluid leak seemed to be a weep, but the test will be when I put everything back together and check under high brake pressure.
I still had to push hard and turn to get the piston back into the cylinder bore on both sides, but the tool I'm using is not well mated to the semi circle cut outs in the end of the piston. However, I do remember when my other car had the problem when it was impossible to turn the piston, so I know what a seized piston feels like.

 

I finished putting the car back together. No apparent leaks with the car running in the driveway. I'll give it some extensive road tests tomorrow.