As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) PILOT REPORTED RT EXHAUST SOUNDS LIKE ITS HITTING STRUT. INSPECTED & FOUND NO EVIDENCE. GND RUN OF ACFT SHOWED CYLINDER NR 3 EGT 800-1000 DEGREES LOWER THAN & CHT CLIMBING AT HALF THE RATE AS OTHERS. SHUT DOWN ACFT & PERFORMED COMPRESSION TEST CONFIRMING NO COMPRESSION ON CYLINDER 3. BORESCOPE INSPECTION SHOWED EDGE OF VLV BURNT & MELTED AWAY APPROX 1CM X 3MM OF THE EDGE OF THE VLV SEAT CYLINDER. REPLACED WITH NEW.