What was found
FLT NR 3183 - CLE-CLE - SHORTLY AFTER TAKEOFF THE LEFT ENGINE OIL PRESSURE DROPPED TO ZERO FOLLOWED BY A LOUD BANG. THE FLIGHT CREW SECURED THE LEFT ENGINE AND LANDED WITHOUT INCIDENT. MAINTENANCE REMOVED AND REPLACED THE LEFT ENGINE IAW EMB-120 MM MAINTENANCE DIRECTIVES NR 7 AND NR 8, AND NR 9. ALL OPERATIONAL AND LEAKED CHECKS WERE GOOD IAW EMB-120 MM 61-00-00 AND 71-00-00. AIRCRAFT WAS RETURNED TO SERVICE. (Z)