As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) NR 4 CYLINDER HEAD FOUND CRACKED WHILE DOING AN UNSCHEDULED VISUAL INSPECTION OF THE ENGINE FORWARD FACE. CRACK WAS NOT DETECTED AT THE LAST INSPECTION 60.3 HOURS BEFORE THIS EVENT. CRACK LOCATED AT EXHAUST PUSH ROD/ROCKER HORN. SERVICEABLE UNIT INSTALLED AND RETURNED TO SERVICE. (X)