As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ATTEMPTED TO START THE AIRCRAFT, ON STARTER ENGAGEMENT A LOUD NOISE WAS HEARD AND THE ENGINE SEIZED. UPON INITIAL INSPECTION IT WAS FOUND THAT THE ENGINE WOULD NOT ROTATE EITHER DIRECTION. AFTER FURTHER INSPECTION IT WAS FOUND THAT MULTIPLE TEETH WERE MISSING FROM THE STARTER ADAPTER GEAR AND A COUPLE WERE STUCK IN THE CAM GEAR THUS NOT ALLOWING THE ENGINE TO ROTATE.