As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) DURING ROUTINE INSPECTION, NR 9 CYLINDER HEAD WAS FOUND CRACKED. CRACK WAS LOCATED ON VERY TOP OF HEAD ON A LINE THAT WOULD CONNECT FRONT AND BACK SPARK PLUGS. CYLINDER WAS REPLACED AND AIRCRAFT INSPECTION COMPLETED AND AIRCRAFT RETURNED TO SERVICE.