I'm having some trouble with the mav while braking. About a month ago I had the same problem, and the idiots from Sears supposedly fixed it. Now the problem came back and don't know what's exactly happening. They replaced the master cylinder and a part from the drums (I don't remember right now). The first time they blew it, it didn't brake at all, I had to pump it like crazy to stop the car so I took the car to them and complained about their crappy job. Next day I take the car and the pedal feels tremendously hard (it never was like that) and I had to kick the damn pedal to brake, cause it didn't brake softly like before. BTW, this is a manual brake mav. 76 mav, Front disks FTW. Today I was going to my place after picking up my gf and the pedal went down all the way. I didn't panic and drove in 1st until I arrived at home. I flipped the m/c cap and both reservoirs are full, WTF??? There are no leaks, no wet tires nor disks nor drums. Maybe I've to bleed the brakes, but why did the pedal became so damn hard to push after the morons "fixed" it???
Rod from the pedal into the master cyl. Does pedal move freely till it stops? Also you may have wheel cylinders or disc's froze up
They probably damaged the MC when they bled it(1st time you went back)Since they replaced parts and didnt bleed anything originally(hence no pedal)MC failed on you due to their stupidity.They bled it in the car, too much pedal travel for bleeding the MC(damaged the pistons and fouled up the compensating port in the MC (hence no pedal/no leaks)Dont go back there.Get a new MC yourself and replace it yourself.Or the rod fell out/off and you have nothing linking the pedal to the master cyl.Do a visual inspection make sure its there and make sure it is locked into the MC,if you can pull it out the clip that holds it in place is missing,you need that clip.Pull the drums and make sure you dont have any frozen wheel cylender pistons either.Over here you only go to sears if you want to be robbed by some dope without a gun or mechanicle knowledge.Good luck compadre,adios.
Yeah total dumba$$es. BTW, I talked with my neighbor (he's a mechanic) and he's going to install power brakes now. I'll let you know how everything worked out.
Power disc brakes have a different rod/pedal stroke length so be careful.Your car is new enough it may have both mounting holes in the brake pedal for the rod to be relocated(not shure)all though you have discs up front stock ,right?? if so the ratio may not be a problem.Either way,good luck,have fun.