What was found
TYS, DURING A SCHEDULED TEST FLIGHT FOR POST C-CHECK EVALUATION, LAV SMOKE EICAS MESSAGE CAME ON IN FLIGHT AT 10000 MSL, DECLARED EMERGENCY LANDING, ORDER NOTED IN AFT CABIN. MAINTENANCE REMOVED AND REPLACED THE O-RING ON THE ZERO CARBIN SEAL ON NR 2 ENGINE, OPS AND LEAK CHECKED GOOD IAW AE3007A SERIES MM 72-25-25, COMPLIED WITH ANOTHER TEST FLIGHT, TEST FLIGHT SATISFACTORY.