What was found
KIN/JFK - FLT JM 017 - DURING START OF NR 1 ENGINE, A VIBRATION WAS NOTED AT 35 PERCENT N2. AT 44 PERCENT N2, THE ENGINE ROLL BACK WITH N2 DECREASING AND EGT AT 320 AND RISING. AN ENGINE CRANK ATTEMPTED WITH NO N2 ROTATION. THE AIRCRAFT RETURNED TO THE GATE AND WAS REMOVED FROM SERVICE FOR REPLACEMENT OF THE STARTER. INVEST BY MAINTENANCE REVEALED THE STARTER HAD SEIZED. THE STARTER WAS REPLACED AND FUNCTION CHECKED SERVICEABLE. AIRCRAFT RETURNED TO SERVICE. (X)