Another "brake help" thread...
Is your brake warning lite on?
Is it functional?
Prove it works, by continuity-tester, and if the Safety switch at the Combination valve is grounding that light, then you will have to re-align the Shuttle valve. If the shuttle valve has been forced to one side by your bleeding efforts, and it has stuck there, and if it has moved towards the front brakes, it will shut them off! which is by design.
But if the valve is centered with NO-continuity to ground, then we can proceed;
Not an A-body switch but you get the idea. Here the shuttle valve is called the "pressure differential valve".
There is a way to divorce the hydraulics from the mechanical system; but you're not gonna like it.
I'll tell you anyway.. It goes like this;
Part-1; the front brakes
1) Get all four corners up, the wheels off, and all the brake hardware off
2.) C-clamp the caliper pistons into the bottom of their bores
3) Remove from the w/cs ,the shoe actuators, then push the w/c pistons into the bores flush with the bodies, then C-clamp them in there so they cannot pop out.
4) pump up the brake pedal until it is high and hard to a moderate effort. Some pedal motion is used up by the workings of the C-port, but not more than one inch, and as soon as that C-port is closed, the pedal should instantly get hard.
5) while there, and without taking your foot off the pedal, add and subtract a little pressure looking for sponginess. If you find it, fix it. If you don't, proceed
6a) take your foot off the pedal and wait at least 5 seconds for the fluid to return to the Master; then press the pedal. If it is still high and hard, then your hydraulics are fine. But if the pedal goes soft again, you have air in the system or crappy flex-lines, or a faulty master. Proof is by process of elimination.
6b) proving the lines is by observing them
6c) proving the air in the system is by observing roiling at the Compensation-Port. If you get a geyser upon release of the brake pedal, there is trapped air, acting like a spring, and forcing fluid back into the master. CAUTION, brake fluid attacks paint, so take steps to contain the geyser, I'm not buying you a new paintjob!
6d) if b an c above are good, that points to bad M/C.
Part-2
10 if everything turns out good, now you can be sure that the hydraulics are good.
11) the next place I would look is to a flexing caliper. I used to have a machined metal block to lay in the caliper, then pump up the brake, to observe the caliper flexing and prove seal retraction is working. The pedal should get hard, and upon release, the piston should be retracted back into the bore, just a few thousands of an inch.When you are satisfied, C-clamp it back in, then move to the other side . When satisfied;
12) get a prybar and figure out how to prove the rotors are properly seated on the spindles. a couple of thousands of movement at the OD are acceptable, but not much more, and they should spin freely, and smoothly. What I'm looking to prove is that the bearings are sized right and that the outer races have been properly seated . You can't have a floppy rotor that keeps loosing it's adjustment.
13) working one side atta time,
13a) Take the pads to a surface-plate and see if the friction surfaces rock. Rocking is unacceptable.
13b) Put two of them together and see if they rock, face to face, which would be unacceptable.
13c) C-clamp two of them together, near the center point. Then with a caliper, make sure both ends measure within a few thou of the same.
13d) fit the pads into the bracket, and see if they move back and fourth fairly easily, to and from the rotor. Clean out the rust as may be required, and try again. When you are satisfied, cuddle them up to the rotor
14) install the caliper making sure all hardware is factory and not bent. pump up the pedal. looking for high and hard. If it is not, it can only be that the caliper is NOT running at 90 degrees to the rotor. Have a friend operate the pedal, while you get eyes on the caliper. if the piston does not contact both ends of both pads simultaneously, then you will see the caliper do a little funky dance, with increasing pressure. If this happens, something is bent, be it the caliper or the bracket; find it, then replace it.
14b) After you are satisfied, take it apart and C-clamp the piston back into the bore, then move to the other side, with the remaining pads, and repeat.
14c) when you are satisfied, reassemble the front system and go look for a high hard pedal.
14d) as said earlier, some dropping of the pedal is normal; up to maybe one inch, as the C-port has to be closed first.
Part-3
the rear brakes. one side atta time
1) relax the parking brake!
2) fit the shoes to the drums. If you can rock them on the brake surface, they are gonna take a long time to break in. If the shoes stick out of the drum laterally, they are wrong
Notice that there are long shoes and short shoes; each side of the vehicle gets one of each.
2a)Most likely you have already installed the parking arm onto the longer rear shoe , I think the pin only fits one way.
2b) the rest you are already intimately acquainted with.
3) since you have noise, look into the drums, at the mounting flanges; witness marks there point to the shoes being too wide or you have excessive axle end-play
4) The Park-brake struts and self adjusters, are side specific. Make sure that they have not been swapped side for side. I forget which adjuster goes on which side but if you get them backwards it's hard to adjust them, and I suppose, they would unwind during use. IDK that, cuz I've never done it, lol. IIRC the adjusters are marked "L" and "R".
5) When yur done installing,
the shoes have to be resting tightly on the anchor pins. If they are not, check that the Parking Brake struts are fully retracted. The parking brake cables have to be adjusted every time you install new shoes; unless you never use them, I suppose, lol.
6) adjust the rear shoes tight to the drum, then back them off a few clicks .
7) the Parking brakes try to adjust themselves every time you back up with the brakes applied. If I had your problem I would defeat this mechanism until this problem is resolved. This is as simple as removing the cable and the spoon.
Once again, Happy HotRodding
Is your brake warning lite on?
Is it functional?
Prove it works, by continuity-tester, and if the Safety switch at the Combination valve is grounding that light, then you will have to re-align the Shuttle valve. If the shuttle valve has been forced to one side by your bleeding efforts, and it has stuck there, and if it has moved towards the front brakes, it will shut them off! which is by design.
But if the valve is centered with NO-continuity to ground, then we can proceed;
Not an A-body switch but you get the idea. Here the shuttle valve is called the "pressure differential valve".
There is a way to divorce the hydraulics from the mechanical system; but you're not gonna like it.
I'll tell you anyway.. It goes like this;
Part-1; the front brakes
1) Get all four corners up, the wheels off, and all the brake hardware off
2.) C-clamp the caliper pistons into the bottom of their bores
3) Remove from the w/cs ,the shoe actuators, then push the w/c pistons into the bores flush with the bodies, then C-clamp them in there so they cannot pop out.
4) pump up the brake pedal until it is high and hard to a moderate effort. Some pedal motion is used up by the workings of the C-port, but not more than one inch, and as soon as that C-port is closed, the pedal should instantly get hard.
5) while there, and without taking your foot off the pedal, add and subtract a little pressure looking for sponginess. If you find it, fix it. If you don't, proceed
6a) take your foot off the pedal and wait at least 5 seconds for the fluid to return to the Master; then press the pedal. If it is still high and hard, then your hydraulics are fine. But if the pedal goes soft again, you have air in the system or crappy flex-lines, or a faulty master. Proof is by process of elimination.
6b) proving the lines is by observing them
6c) proving the air in the system is by observing roiling at the Compensation-Port. If you get a geyser upon release of the brake pedal, there is trapped air, acting like a spring, and forcing fluid back into the master. CAUTION, brake fluid attacks paint, so take steps to contain the geyser, I'm not buying you a new paintjob!
6d) if b an c above are good, that points to bad M/C.
Part-2
10 if everything turns out good, now you can be sure that the hydraulics are good.
11) the next place I would look is to a flexing caliper. I used to have a machined metal block to lay in the caliper, then pump up the brake, to observe the caliper flexing and prove seal retraction is working. The pedal should get hard, and upon release, the piston should be retracted back into the bore, just a few thousands of an inch.When you are satisfied, C-clamp it back in, then move to the other side . When satisfied;
12) get a prybar and figure out how to prove the rotors are properly seated on the spindles. a couple of thousands of movement at the OD are acceptable, but not much more, and they should spin freely, and smoothly. What I'm looking to prove is that the bearings are sized right and that the outer races have been properly seated . You can't have a floppy rotor that keeps loosing it's adjustment.
13) working one side atta time,
13a) Take the pads to a surface-plate and see if the friction surfaces rock. Rocking is unacceptable.
13b) Put two of them together and see if they rock, face to face, which would be unacceptable.
13c) C-clamp two of them together, near the center point. Then with a caliper, make sure both ends measure within a few thou of the same.
13d) fit the pads into the bracket, and see if they move back and fourth fairly easily, to and from the rotor. Clean out the rust as may be required, and try again. When you are satisfied, cuddle them up to the rotor
14) install the caliper making sure all hardware is factory and not bent. pump up the pedal. looking for high and hard. If it is not, it can only be that the caliper is NOT running at 90 degrees to the rotor. Have a friend operate the pedal, while you get eyes on the caliper. if the piston does not contact both ends of both pads simultaneously, then you will see the caliper do a little funky dance, with increasing pressure. If this happens, something is bent, be it the caliper or the bracket; find it, then replace it.
14b) After you are satisfied, take it apart and C-clamp the piston back into the bore, then move to the other side, with the remaining pads, and repeat.
14c) when you are satisfied, reassemble the front system and go look for a high hard pedal.
14d) as said earlier, some dropping of the pedal is normal; up to maybe one inch, as the C-port has to be closed first.
Part-3
the rear brakes. one side atta time
1) relax the parking brake!
2) fit the shoes to the drums. If you can rock them on the brake surface, they are gonna take a long time to break in. If the shoes stick out of the drum laterally, they are wrong
Notice that there are long shoes and short shoes; each side of the vehicle gets one of each.
2a)Most likely you have already installed the parking arm onto the longer rear shoe , I think the pin only fits one way.
2b) the rest you are already intimately acquainted with.
3) since you have noise, look into the drums, at the mounting flanges; witness marks there point to the shoes being too wide or you have excessive axle end-play
4) The Park-brake struts and self adjusters, are side specific. Make sure that they have not been swapped side for side. I forget which adjuster goes on which side but if you get them backwards it's hard to adjust them, and I suppose, they would unwind during use. IDK that, cuz I've never done it, lol. IIRC the adjusters are marked "L" and "R".
5) When yur done installing,
the shoes have to be resting tightly on the anchor pins. If they are not, check that the Parking Brake struts are fully retracted. The parking brake cables have to be adjusted every time you install new shoes; unless you never use them, I suppose, lol.
6) adjust the rear shoes tight to the drum, then back them off a few clicks .
7) the Parking brakes try to adjust themselves every time you back up with the brakes applied. If I had your problem I would defeat this mechanism until this problem is resolved. This is as simple as removing the cable and the spoon.
Once again, Happy HotRodding