Is this a master cylinder malfunction?

[chevyaddict]

Howdy y'all. I have a question regarding my 68. I had to replace one of my calipers (front driver's side). No problem. Did that, bled the brakes, got all the air out. But now it feels like there is something generally wrong with the braking. The brakes have never worked great on the car to begin with, and now the pedal goes way down and the braking power is really weak. My question is, is this a master cylinder problem? What I typically know about failing master cylinders is that when the seals inside begin to go your pedal will slowly depress to the floor while holding the pedal. But what if you just don't get much pedal in the first place? The car does not have power brakes. Any advice would be appreciated. I have not replaced the master cylinder since I've owned the car, and that has been since 1999.

 

[LLC5]

I would say that you either have air in the system or a bad master cylinder. I would bleed/flush all 4 calipers thoroughly and recheck. It is possible if you bled the replacement caliper by pushing the brake pedal to the floor, you may have damaged the seal in the master cylinder. Good luck with it.

 

[frank_nesta]

I would say that you either have air in the system or a bad master cylinder. I would bleed/flush all 4 calipers thoroughly and recheck. It is possible if you bled the replacement caliper by pushing the brake pedal to the floor, you may have damaged the seal in the master cylinder. Good luck with it.

I agree. First bleed the system. If the problem persist go for the master cylinder.