I'm disappointed in my brakes and need to do something about it. (disc front , drum rear) I have said before my pedal seemed to be to low when I applied the brakes. Now after it sat for a while (engine/trans swap) they are worse than ever. Two things I have noticed is 1, I think I'm only getting front brakes. 2, For some reason my master is full to the top, it wasn't that way before. I always kept it about a 1/4 inch below the cap. I want to upgrade to a better master IE: 89/90 Ranger and rebuild my rear drums with new parts... What else should I do ?
I have 76 mav front disc and stock rear drum.. I installed the front disc brakes 3 years ago with all new parts, I replaced my front pads last year because old ones rattled... the rear had new hardware shoes and wheel cylinders 3 years ago... all new rubber lines front and rear...
Do u have the shoes adjusted close to the drums? All the parts springs, etc in proper location? I wud pull drums and make sure all parts are in proper location; if u haven't already. Other than that, the mc may be defective or wrong mc.
Is it a two chamber master cylinder like this? The disks need more fluid and work off of the larger chamber. Did you change the proportioning valve or leave it stock (drum/drum)?
Excessive pedal travel in a disc/drum system is almost always related to the rear brakes... Can be as you suspect, not functioning or badly out of adjustment... Since fluid level has risen, I'd suspect the check valve in the MC has failed which has allowed the brake shoes to retract back into the wheel cylinder, rendering them useless... The one fly in this theory, they should pump up with two or three jabs on the pedal... If one of the cups inside the MC has failed that could cause your issue, as pedal would never pump up or likely sink quickly again if it did...
I can pump them all day long hight never changes. I looked at the wheel cylinders while i had the rear drums off,no leaks. I'm going to replace the rear drums with new,just because that is the only thing I didn't do last time. I think it's either a blocked brake line or the master cylinder...
When I apply the brakes the pedal is about 3" off the floor. the pedal acts the same as when the brakes worked well, I don't think the rear brakes are being activated anymore.
I think changing the mc will solve the problem. I don't think a drum/drum on a disk/drum setup is the way to go. If u had very weak expulsion of fluid when bleeding the rear wheels wud indicate a possible line issue, seeing as everything else is new. Also, rust fluid might indicate rusty/blocked lines.
