As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
OVER LAST 200 HOURS, CYLINDER HEAD SEPARATED ON 3 CYLINDERS IN FLIGHT OR ON TAKEOFF. THE 4TH CYLINDER HAD STAINS AND LEAKAGE AND REMOVED BEFORE FAILURES, BUT WAS NOT BETWEEN NR 2 AND NR 3 FIN PER AD 78-08-07. IT WAS LEAKING BETWEEN TOP STEEL FIN AND NR 1 ALUMINUM FIN. NONE OF FAILED CYLINDERS SHOWED LEAKAGE PRIOR TO FAILURE.