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Discussion Starter · #1 ·
When I got my 68 P1800 the dual circuit master cylinder was leaking from behind but the brakes functioned as they should with no pulling or sticking. I then changed the master cylinder with a newly rebuilt one and I went ahead and changed the brake shoes in the rear drums, the front calipers and brake pads as well. I then bled the entire system. The problem I am having now is that the rear brakes seem to lock up when I stop at a light and hold on to the brakes. When I let them go and drive I can feel the rear brakes hold on and then let go suddenly. What could it be? I have checked the rear drums for leaks and kinked lines, but nothing. i have also rebled the system using a Might Vac as well as the prescribed bottle method and still nothing. Any ideas?
 

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Stuck relief valve in the master. Who rebuilt it?
 

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Discussion Starter · #3 ·
Thanks for the response tmtalpey! And I'm not sure who rebuilt it to be honest, I got it from an auto parts store that required me to bring my old one in. But I'm ready to return it, get my money back and find another one online somewhere. Any good sources? Don't want to go through this again lol
 

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How old are the rubber brake hoses? Over time they swell up inside like your arteries and eventually close up even though they look just fine from the outside. Applying the brakes works because there is enough pressure to overcome the blockage, but the brakes then will not release because the fluid can't come back out. It's very common on old cars. If you are unsure of their age, just replace them all. They are cheap and generally easy to replace.
 

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Discussion Starter · #5 ·
Thanks twisted tree! From what i can tell, all of the rubber hoses were replaced with steel braided hoses and new rubber hoses from the previous owner. What I have done is order a new master cylinder that is the correct placement (Vertical) from IPD. The master cylinder i bought may have been for a 69 since it is horizontally mounted and it isn't the correct one for the vehicle. I came to the conclusion that the master is a good place to start since i noticed that the one on the car wasnt correctly mounted. I figured i should start with the basics. Ill update you guys once i install the new master and test it again.
 

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Discussion Starter · #6 ·
So I replaced the mastercylinder this past sunday with the new one from IPD. I didnt get a chance to bleed the brake system as of yet but the brakes already feel better and a test ride on the street revealed that the brakes are still sticky but not as much as they were before which gives me the impression that after bleeding the brakes they wont stick, atleast I hope they wont stick. I will update you guys once i bleedem!
 

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Discussion Starter · #7 ·
Ok so i bled the brakes and they are much better! But i am sorry to say that i still have sticky rear brakes. My next step is to replace the wheel cylinders since they were rebuilt but i didnt have alot of faith in the rebuild kits quality. anyone have any other ideas? Thanks for the help!
 

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Discussion Starter · #8 ·
PROBLEM SOLVED!-I replaced the rear wheel cylinders with brand new cylinders from IPD and the car is driving like a dream. The rebuild kits were not working as good as new parts do. So in my effort to save $30, i caused myself a lot more aggravation. Lesson learned for next time!
 
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