front disc brake problem

[stick]

the front calipers will freeze up on me after braking about 5x. i then have to release the pressure at the master cylinder by loosening the lines and the calipers release. i then start all over again, use the brakes 5x and then the fronts freeze. could this be the master or the proportioning valve. i'm using the mopar performance master. thanks

[71charger_fan]

How are your front hoses? If they're old, they might be collapsed internally.

[stick]

everything is new

[resq302]

sounds like the master isnt returning and all you are doing is pumping up pressure into the system.

[John_Kunkel]

  The rear piston in the MC is used for the front brakes and if the pushrod adjustment doesn't allow the piston to fully retract the compensating port will be covered and prevent the fluid f rom returning to the MC.

If it has manual brakes you need to shorten the pushrod; if power, the rod in the booster needs to be shortened likewise.

[resq302]

could also be rust build up or a metal shaving that is preventing the piston inside the master cyl to move all the way back to its resting state.