okay, my rear brakes are still not working right. I put new rear calipers, pads, and ebrake cables today and the brake pedal goes half way to the floor before the brakes start working and the brake light is on. there is no air in the lines, they've had the hell bled out of them 2 or 3 times. I was wondering if it could be the master cylinder. I got a good master cylinder and prop valve from an 87 GTA and was wondering if they would work. i'm pretty sure the master cylinder will, but not positive about the prop valve. I also noticed when we were bleeding the brakes that there's a gurgling sound coming from the master cylinder when you pump the brakes. think the master cylinder is bad?

 

btw, 85 iroc-z. 4-wheel disc brakes. forgot to mention that.

 

From my own personal experiances, a gurgling sound as you put is never a good thing. Esp. coming out of a master cylinder. Try to rebleed the brakes and ask a buddy to watch the master cylinder and see if there are bubbles coming up. If there are, you have a leak in the master cylinder and its time to replace or rebuild. I would just replace it as they arent all that expensive.

 

The brake light only comes on when the line pressure is low.. that would suggest that you have air in the lines (which you said is unlikely), that there is a leak (possible), or that the master cylinder is bad, yours is 18 years old (out of an 87 16 years old), rule of thumb when working on brake systems as old as ours is that you might as well replace/rebuild the master cylinder if the system is open since it is good insurance. The proportioning vlvs don't usually go bad.. the one from the 87 will work provided the fittings match up which I am not sure of... I know they changed from year to year.

Go with Aklaims reccomendation, rebleed (I had the same problem when I switched to discs turns out I needed to rebleed the brakes again even when I thought I didn't), check for leaks, if none go with the new master cylinder.

 

hey thanks for your replies. i did replace the master cylinder and that fixed the problem. It looked the same but the prop valve wasn't even close but it didn't need changed. Oh well, at least i have a working e-brake now too.....

 

It could have been possible that there was air in the master cylinder which would have required a bench bleeding off the car. Oh well, seems you fixed it anyway.

 

glad you got it fixed!!! we all need good brakes!!!