I recently bought a really clean 1997 ford explorer with 140xxx miles. The fuel pump was bad, so i replaced that. I went to start it, and it fired right up, but like five minutes later, the head gasket blew. Is this just bad luck, or could the two be related?

 

From my experience, I would say they are not related, but anything is possible.
What happened to cause you to determine a head gasket problem ?