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I bled all my brakes and now they are all locked up, any ideas why? I used a Motive power bleeder. There is no pressure on the brake pedal and the fluid level is between the reference marks in the resevoir. My ideas are that the pistons are seized from corrosion - this seems unlikely however, or that there is some sort of check valve in the system that is not allowing the pressure to release with release of the pedal. Any help appreciated.
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All 4 corners, I bled using the power bleeder and the bleeder valves. I did nothing with the pads as they have good thickness, I have since taken off the left rear caliper but haven't disconnected the line or tried to push in the piston, maybe tonight. BTW the caliper I took off is supported so it isn't hanging by the line - thanks.
Don't know I guess, but the wheels turned. I took the wheels off, and bled the brakes. I have never driven the car but they rolled it off the flatbed into my garage so I know they weren't locked up when the car arrived. I have turned the rear axles by hand with the rear jacked up before I started working on the engine. On the one caliper I have removed there was a lot of dirt and rust between the pad and the caliper, for all I know the pads are the factory originals or at least haven't been changed for many years.
this kind of sounds like what i went through about a year ago, after a lot of trial and error, my problem broke down to the seals in the master cylinder not uncovering the return ports after the brakes were released.

i know this sounds crazy, but my problem cropped up after i had driven the car at least 40 miles right after buying it. also, the prior owner didn't have this problem.

look at for a much better explaination than i am capable of regarding the return ports and pushrod length.

someone on this forum has suggested loosening the 4 nuts that hold the m/c to the booster a bit at a time and inserting a temporary spacer (i think the original post mentioned stacking quarters) until the brakes release, and then adjusting the push rod to that length.

also, there can be a lot of crud in the system, last spring i flushed and bled the system a number of times, and this winter when i drained the m/c lots of crud was in it. crud could be blocking the return ports.

good luck

Okay, a non-driver when you got it. Sitting for how long?

My best guess, your calipers have varnished/gummed up pistons.

Nice thing is the pistons are stainless steel, so they should be okay. Bad thing is they can now be a PITA to remove.

Fronts are two piece calipers. DO NOT TAKE THE TWO HALVES APART. There is an o-ring seal that IS NOT included in the rebuild kits. You should be able to rebuild with them together.

Rebuild kits at any vendor. Remove caliper, still connected to hose. Remove pads. Wood block two opposing pistons. C clamp third piston. Put caliper in plastic bag and then in a large tub. Hit the brake pedal until piston comes out. Clean up fluid mess. Remove old dust seal. Scotchbrite varnish, etc. Install new piston seal. Install piston. Install dust seal. Repeat as needed.

Bead blast calipers, paint them, replace bleeders with speed bleeders. If you can get the old ones out, that is. Choices are yours.

Or it could be a sticky MC if you get lucky.

good luck,

Originally posted by LF - TP 2511:
Fronts are two piece calipers. DO NOT TAKE THE TWO HALVES APART. There is an o-ring seal that IS NOT included in the rebuild kits. You should be able to rebuild with them together.

I rebuilt mine last year and the rebuild kit I got from Byars had everything, including the o-ring. I also don't know how you would go about properly cleaning the caliper if you didn't split the halves.
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