As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ROCKER STUD BACKED OUT CAUSING EXCESSIVE VALVE CLEARANCE WHICH CAUSED THE PUSHROD TO GET JAMMED AND BENT. CYLINDER WAS IN C/W SB 412B (AD 77-20-07) WHICH REQUIRES STUDS TO BE LOCKTITE INTO POSITION. CYLINDER WAS MARKED IAW THIS PROCEDURE. SUBMITTER SUGGESTS BETTER WAY OF SECURING STUD.