As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) WHILE CARRYING OUT SERVICE BULLETIN CSB98-1B, THE OUTER VALVE SPRINGS ON NR 2 CYLINDER INTAKE AND EXHAUST, AS WELL AS ON NR 1 CYLINDER INTAKE VALVE WERE FOUND BROKEN. THE SPRINGS WERE REPLACED AND THE AIRCRAFT WAS RETURNED TO SERVICE.