Dad blew his motor yesterday on his '00 426. He said it make a terrible sound at low RPMs as he was accelerating coming out of a turn for a jump, so he stopped and shut the motor off. Now it will not kick over. It's a 2000 model, NEVER been apart... I wished he'd had rebuilt it last year, but he didn't want to. Oh well! What are some possible things that may have gone wrong? I'm thinking valvetrain somewhere. I doubt the cam cahin broke (like mine did), cause it was still running, but making a bad sound. I guess it's POSSIBLE he jumped a tooth or something, which could have jammed a valve into the piston. There is no visible external damage - so hopefully it won't be too bad of a rebuild. But what do you guys think??