Locked up brakes

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kenneth1669

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My passenger side brake is sorta locked up. It still moves when I spin it but it’s not fully free. From what I have researched my problem could be a seized caliper, the proportioning valve is doing vlave stuff or the brake line is acting as a one way valve. So to fix all those I bought a new caliper, that didn’t work. It’s not the proportioning valve because the other brake stil kinda works, and I was able to bleed the front brakes. for the brake line I took it off and poured water through it both ways and it came out so I’m pretty sure that means it’s fine but it’s in rough condition so depending on what you guys say I’ll get a new one. I don’t know where to go from here. Then at he driver side rotor will spin freely for about half a turn and then gets lots of friction. I’m thinking the rotors warped but all the brakes, calipers, and fluid have less than 500 miles on them.

I hope that wasn’t too confusing I kinda just dumped what I was thinking on the forum so if you need clarification on anything please ask. Anything would help. Thanks
 

Scott91370

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Warped rotors usually don't keep the pistons from releasing. I would bet on a bad hose. Even though low pressure water went through (which could create another issue with brake fluid) that doesn't mean it isn't colapsing. And at 35ish years old you'll feel better about it.
 

Radiohead

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That's the thing with our beloved squares, like us, we're all getting up there in age. Rubber parts just aren't meant to be good 40+ years into it.

Same thing with fuel lines and suspension bushings, these things just can't stay fresh this long. I'm also going to say it's time for the hoses to go, both front AND the one at the rear axle. Rotor warp is from excessive heat, which a sticky caliper will generate. So, to not ruin what you already have done, finish the job and you will never have to worry about it again.

Just a reality of ancient vehicles. One many overlook.
 

kenneth1669

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Definitely change the hoses. Also check all the caliper hardware, sliders etc. for freedom of movement.
should it be pretty lose or have some stability?
 

Blue Ox

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How to describe how much "loose"....? Hmmm.

With the piston retracted you should be able to move the caliper back and forth with hand pressure. The sliders ride on O-rings, so expect some drag, but it shouldn't require savage force. It should move linearly. No wobbling, rattling, twisting, binding or significant spring-back.
 

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How to describe how much "loose"....? Hmmm.

With the piston retracted you should be able to move the caliper back and forth with hand pressure. The sliders ride on O-rings, so expect some drag, but it shouldn't require savage force. It should move linearly. No wobbling, rattling, twisting, binding or significant spring-back.
That's what she said.
 

Finkaire

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Rear brake lockup! I gave up and took it to a shop. Got it back with the brakes dragging. After three attempt and a bunch of money they work. There is confusion on the OE setup, I’m the original owner. Supposedly they couldn’t find wheel cylinders that matched? Brake line swapped did the final trick. I believe next time for about the same cost I’ll retrofit to discs. Sorry for the double post
 

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