Small Engines (Lawn Mowers, etc.): Mower Stops Running!, metal flakes, john deere stx 38

Question
Hey Paul,
We have a John Deere STX 38.
I was cutting my lawn yesterday.And the Mower stopped running.
I took the deck off checked the belt and noticed metal flakes.(On top of the deck)
Replaced deck got mower running again,but when you engage the blade it wants to cut off.
What could be the cause of this?
And how hard to repair?

Answer
Really the only place the flakes can come from is the PTO clutch its self.  Leave the deck belt off and see if the mower dies when you engage the blades. Do you loose spark when it dies?  Is the shutoff instant or does the engine just peter out?  Looking forward to more info. We can fix this.  Also do you have a yellow or black deck?  When the top (primary belt) is off of the mower does the deck spin freely?  if it does you know you have a tractor problem.  If no, you have a deck problem.  Remove the lower (secondary) belt and find the seized component.