As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
NR 3 CYLINDER CRACKED CIRCUMFERENTIALLY APPROXIMATELY 4 INCHES BELOW THE HEAD. THE RESULTANT VIBRATION MADE A PRECAUTIONARY LANDING PRUDENT. UPON REMOVAL AND INSPECTION, THE CRACK APPEARED TO VARY BETWEEN 0.060 INCH AND 0.030 INCH (APPROXIMATE) AS IT PROPAGATED AROUND THE CYLINDER.