What was found
HPN - NORMAL TAKEOFF EN ROUTE BAHAMAS. APPROX 1 HR EN ROUTE AT FL 310, PILOT NOTED NR 1 ENG VIBRATION INCREASE FROM .3 M/S TO .6 M/S AND INCREASE IN ENG NOISE. ALL OTHER ENG INDICATIONS WITHIN NORMAL PARAMETERS. ENG NOISE SUBSIDED THEN INCREASE IN ENG VIBRATION FROM .6 M/S TO .9 M/S, WITHIN NORMAL LIMITS. PILOT DISCONTINUED FLT, PRECAUTIONARY LANDING AT ISP. BORESCOPE INSP REVEALED NR 2 TURB DISC DAMAGE. ENG REMOVED AND REPLACED. UPON ENG DISASSY AND REPAIR, ALLIED SIGNAL NOTED A GAS PRODUCER SPACER WAS INSTALLED. SPACER CONFIG IS NOT COMPATIBLE WITH ALF502L-2C ENGINES AND THEY SUSPECT ENG DAMAGE A DIRECT RESULT OF INSTALL OF INCORRECT GAS PRODUCER SPACER CONFIG. ENG REPAIRED AND RETURNED TO SERVICE.