As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BOLT HOLE ELONGATED ON DRIVE-END OF FRAME, CESSNA KIT, AK210-54D. BOLT WAS NOT TIGHTENED ENOUGH AND ALLOWED MOVEMENT OF DRIVE-END FRAME. ENGINE VIBRATION CAUSED FRAME TO MOVE AND ELONGATE HOLE BY .1250 INCH PLUS. DRIVE-END FRAME WAS WORN AWAY WEAKENING FRAME THAT SECURED ALTERNATOR TO MOUNTING BRACKET.