What was found
(CAN) RT ENGINE OIL PRESSURE PROBLEMS WERE NOTICED DURING ENGINE RUN-UP. NR 2 CYLINDER PISTON WAS F OUND CRACKED AND THE LOWER SKIRT OF PISTON FOUND IN OIL PAN. CYLINDERS WERE REMOVED & ENGINE INSPECTED. REMOVAL OF CYLINDERS & PISTONS REVEALED OTHER CRACKED PISTON SKIRTS THAT HAD NOT YET FAILED. WE SUSPECT THAT THIS IS A BAD BATCH OF PISTONS AND ANY ECI CYLINDERS AND PISTONS ARE BEING REPLACED. THE AIRCRAFT IS STILL UNDERGOING MAINTENANCE TO INVESTIGATE THE PROBLEM WITH THESE CYLINDERS AND PISTONS.