Ok, so my front deck John Deere F725 just wouldn't crank the other day. I notice the fuel filter is dry......so I'm thinking it's the fuel pump. Before I pull the pump, I take off a valve cover and spin the engine over. There is no valvetrain movement at all. So it has to be a broken camshft......Correct??? The machine has roughtly 2,000 hours on it. Anyone have any clues or experience with this engine before? How costly could this be to fix? How much other damage could there be as far as valve hitting pistons because of being out of time? Is this even an interfearance engine? So many quesitons.....please help. THANKS!