As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(AUS) ENGINE EXHAUST VALVE STUCK OPEN. TWO OTHER VALVES ALSO STICKING.DURING RECTIFICATION FOR THE STICKING VALVES IT WAS NOTICED THAT THE CARBURETTOR BUTTERFLY SHAFT TO BUSHING FITTING SEEMED EXCESSIVE (EXCESSIVE END FLOAT AND AXIAL WEAR).