What was found
AFTER COMPLETION OF NR 4 PROPELLER INSTALLATION GROUND RUN WITH ENGINES IN HIGH SPEED GROUND IDLE AND POWER LEVERS IN GROUND RANGE MAINT PERSONNEL NOTED HEAVY, ABNORMAL VIBRATION. SHUTDOWN NR 4 ENGINE WITH EMERGENCY HANDLE AND VIBRATION CONTINUED. VIBRATION CHANGE NOTED WITH NR 1 ENGINE POWER LEVER MOVEMENT. SHUTDOWN NR 1 ENGINE WITH EMERGENCY HANDLE AND VIBRATION CEASED. FOUND NR 1SPINNER HAD DEPARTED AIRCRAFT, DAMAGING 2 NR 1 PROPELLER BLADE CUFFS, DUE EXCESSIVELY WORN RESERVOIR ADAPTER THREADS. REPLACED NR 1 PROPELLER, SPINNER AND RESERVOIR ADAPTER. INITIATED FLEET CAMPAIGN ITEM TO CHECK RESERVOIR ADAPTER THREADS FOR EXCESSIVE WEAR.