What was found
(CAN) ON THE CARBURETOR AIR BOX BOTTOM ASSY COVER THERE ARE TWO FELT STRIPS SECURED WITH 6 STAPLES. AS THE FELT WORE, THE WIRE STAPLES BECAME LOOSE AND FELL OUT AND LODGED IN THE THROTTLE BORE AT THE BUTTERFLY VALVE (P/N 87327003). THIS PREVENTED THE PILOT FROM REDUCING POWER. AN IN-FLIGHT SHUTDOWN WAS NECESSARY. THE SUBMITTER SUGGESTS SECURING THE FELT STRIPS BETWEEN RIVITED ALUMINIUM WOULD ELIMINATE THE PROBLEM.