What was found
WE WERE CONTRACTED BY AN INSURANCE BROKER TO REMOVE ENGINE FROM A BEECH E35 (N3473B) AFTER IT FAILED DURING THE ENGINE'S FORTH GROUND RUN UP AFTER THE ENGINE WAS O/H AND ALL CYLINDERS WERE REPLACED BY MAINTENANCE AT AIRPORT. DURING THE ENGINE REMOVAL WE FOUND FRONT-LEFT CYLINDER NR 6 AND FRONT-LEFT ENGINE MOUNT SEPARATED FROM ENGINE CRANK CASE. THE CRANK CASE WAS BROKEN OPEN OVER THE TOP BETWEEN FRONT-LEFT CYLINDER NR 6 AND FRONT-RIGHT CYLINDER NR 5. AS A RESULT SIGNIFICANT DAMAGE WAS INCURRED ON THE AIRFRAME FRONT-LEFT ENGINE MOUNT. OTHER DAMAGE WERE INCURRED TO THE NOSE BOWL, TOP COWLING AND POSSIBLE OTHER AIRFRAME STRUCTURE. PICTURES ARE AVAILABLE. REASON FOR FAILURE: UNKNOWN. LOCATION: CENTERVILLE MUNICIPAL AIRPORT, IA (KTVK). DATE OF VISIT: 12/22/2020.