Master cylinder problem

[John S. Lagnese]

Hi,
I ordered and received my master cylinder. It turned out to be the wrong 
one. I'll go back tomorrow to try again.
I don't see how this could cause the front passenger side brake to freeze 
up. It displays all of the symptoms laid out by others. It doesn't happen in 
winter, occurs almost every time when the car is hot, and goes away when the 
mc cools.
What I don't see is if there are two lines coming out of the mc, how can 
one, but not two wheels be affected?
Thanks,
John