Seized Brakes

[Ozzie831]

OK... im new to the site wooo. i bought a 77 280z about 3 months ago and everything ran perfect till i noticed that one of my brake lines was a little messed up in the rear about 3 weeks ago so i bought the stainless steel breaklines off of thezstore. after i put them on everything seemed all right then my driver side caliper started seizing on me so i went to pick and pull and got another caliper and it started seizing also. so i said screw it and bought new remanufactured ones off the z store about a week ago and i just put em on today. now after doing all that both of my calipers are stuck and i have no idea why. so any opinions are greatly appreiciated. in any correlation this only started happening after i got the new lines if thats means anything

[johnc]

Well, its obviously not the calipers.

 

Sounds like to the master cylinder piston is not retracting all the way allowing brake fluid to return from the calipers into the reservoirs. Check the pushrod between the brake booster and the master cylinder first.

[JMortensen]

Usually if the master cylinder is not retracting the problem is easily identifiable because the problem gets worse and worse as you drive and the fluid gets hotter and hotter. If you let the car sit for a couple hours or overnight, the brake fluid cools and then you would have normal brakes again. Same thing would happen again the next time you drove. You could also crack a bleeder when the brakes are seized and it should squirt out like someone is pushing on the brakes. You should have about 1/8" of pedal travel before the pedal engages the booster, and I don't know the spec of the rod inside the booster, but what you really need is COMPLETE retraction of the master cylinder pistons.