Front brakes grabbing - pedal barely moves

[KnuckleDragger]

Okay - my '69 Charger (all drums) front brakes GRAB! New master cylinder, new booster. I can't adjust them either. There is no gradual braking. I had to adjust the MC push rod almost all the way out. When I brake, the pedal barely moves. If I adjust the push rod in, then the pedal goes a long way... but there still isn't any gradual braking. Also... in reverse the brakes are horrible.
they've been bled.

 

[bigmanjbmopar]

Pictures of the set up? Is the MC dual cup 1 big 1 small? or both same size?

 

[Jim Bob The Dancing Bear]

Pics of the master with the lines to distribution block and bore of MC will help everyone answer intelligently.

 

[Cranky]

Is the booster getting too much vacuum? Isn't it supposed to be regulated.....?

 

[318 Six Pack]

It has been a long, long time, but around 1979/1980 my 1973 Dart (drums all around) did something pretty similar not long after a front brake job. One of the brake shoes had fallen off of the metal and was flopping around in the drum, IIRC.

 

[bigblock]

I had a reman booster do that. The brakes were untouchable. Unplug the vacuum source and they were hard but usable.

 

[khryslerkid]

Sounds like your rod is adjusted too long, activating just the front brakes...

 

[KnuckleDragger]

Here is the pic of my MC.
The front brakes grab. It's basically all or nothing. The pedal barely moves before the brakes engage. If I adjust the push rod in at all, then the pedal goes almost the the floor, with no braking... and then the front brakes grab. Also - in reverse the brakes don't work well.

 

[Jim Bob The Dancing Bear]

What was the condition of the brakes before the new master and power brake booster? What was the reason you purchased a new master and booster?

 

[Green72Runner]

you said you put in a new MC and Booster, have you taken the drums off to inspect in there? All look fine? Leaky wheel cylinders will cause brake grabbing.

 

[challenger6pak]

How are your brake hoses? I have had them partly plugged in a car and it did the same thing your car is doing.

 

[KnuckleDragger]

What was the condition of the brakes before the new master and power brake booster? What was the reason you purchased a new master and booster?

I bought the car to restore. The booster was old and shot, so I bought a new one and it came with a MC. I also put new shoes all the way around.

- - - Updated - - -

How are your brake hoses? I have had them partly plugged in a car and it did the same thing your car is doing.

Not sure about the hoses. I've bled the lines, and fluid seems to flow through them fine.

- - - Updated - - -

you said you put in a new MC and Booster, have you taken the drums off to inspect in there? All look fine? Leaky wheel cylinders will cause brake grabbing.

I'll pull all the wheels off again to check the wheel cylinders.

 

[440+6]

Are the shoes installed correctly, larger shoe towards rear of car? I never had an all drum car, just guessing.