As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
NR 3 EXHAUST VALVE TO GUIDE CLEARANCE WAS FOUND TO BE .012". BELOW ACCEPTABLE MINIMUM TOLERANCE OF .015". 201 HOURS TIS SINCE SB 388C HAD PREVIOUSLY BEEN PERFORMED. VALVE CLEARANCE MEASUREMENT HAD BEEN .020". VALVE HAD TO BE DRIVEN OUT TO REMOVE IT FOR REAMING OF THE GUIDE. AFTER REAMING THE NEW CLEARANCE WAS FOUND TO BE .022".