Why don't the breaks on my 82 Chevy Silverado disengage when they are warm?

[racerski2]

I recently replaced the booster on my 82 Silverado. During the first few miles when the breaks aren't warm everything works normally. After the breaks heat up it acts as if they won't disengage. The break peddle also feels stiff and only moves 1/2 from it's normal position. After the breaks cool, everything is back to normal. Can anyone help me?

[Dr. Car Guy]

I agree, adjust the pushrod on the booster.