What was found
(CAN)PILOT REPORTED ENGINE STOPPAGE (2-3 SECONDS) DURING TURBULANCE; THEN RETURNED TO NORMAL THERE HAVE BEEN 3 OR 4 OF THESE OCCURRENCES OF THIS TYPE IN THE LAST 100 HOURS, THESE HAPPENED DURING BOTH SMOO TH AND ROUGH AIR. DURING TROUBLESHOOTING THE PROBLEM LYCOMING SERVICE INSTRUCTION 1398A SURFACED AND IT INDICATES A MODIFICATION TO THE CARBURETOR DURING ROUGH AIR. THE S/I INVOLVES THE CHANGE OF THE VALVE ASSEMBLY. THE AIRCRAFT IS CURRENTLY UNDERGOING TESTS TO DETERMINE IF THE PROBLEM HAS BEEN RECTIFIED.