As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
APPROXIMATELY 2 INCH RADIAL CRACK IN CYLINDER HEAD ADJACENT TO AND OUTSIDE OF THE INTAKE VALVE. EXTERNAL EVIDENCE OF EXHAUST GASSES ESCAPING FROM CRACK WAS PRESENT AND COMPRESSION TEST PRODUCED FREE FLOW OF SHOP AIR FROM CYLINDER HEAD BETWEEN THE 9TH AND 10TH HEAD FINS ON THE INTAKE SIDE.