So I installed the 96' master cylinder in my 89' cherokee. It worked well at first now there's a popping in the rear wheel. I bled the brakes again now there is also an intermittent popping in what sounds like the front caliper. Also the rear passenger brake seizes up now so I'll be putting in a new wheel cylinder. What could be causing the popping?

 

Pull the rear drums off and have a gander in there.

 

^ what he said