What was found
(CAN) PROPELLER WAS LEAKING OIL OUT OF CYLINDER. TRAVELLED TO AIRCRAFT, FOUND PISTON TO CYLINDER SEAL, ITEM 40, IPL FIG 3, APPEARED TO BE TWISTED AND SPLIT. IT FELL OFF OF PISTON WHEN CYLINDER WAS REMOVED. REPLACED SEAL, REINSTALLED CYLINDER, NO LEAKAGE EVIDENT WHEN BETA TUBE REINSTALLED AND FLIGHT IDLE ANGLE SET.ENGINE TEST RUN, NO LEAKAGE.AIRCRAFT FLOWN FOR APPROXIMATELY 2 HOURS AND NO LEAKAGE FOUND AFTER FLIGHT.