What was found
IN CRUISE AT FL430, FELT A VIBRATION & RUMBLING. AFTER ABOUT 20 SECS, OBSERVED AN ENG VIBRATION L AMBER CAS MESSAGE. OBSERVED AN LT ENG ITT EXCEED & A RED ENG FAIL L CAS MESSAGE. VIBRATION CEASED & DIVERTED & LANDED. REMOVED & INSTALLED REPAIRED ENGINE, IAW AMM 71-00-01. C/W SATIS WET MOTOR OF LT ENG IAW AMM 71-00-01. C/W SATIS DRY MOTOR OF LT ENG IAW AMM 71-00-01. C/W SATIS LT ENG IDLE RUN, LEAK CHKD LT ENG, NO LEAKS IAW AMM 71-00-01. C/W SATIS PWR ASSUR RUN ON LT ENG IAW LMM 72-00-00. C/W SATIS OPS CHK OF LT TR IAW AMM 78-30-00. OPENED LT LWR COWL. INSP ENG FOR LEAKS, NONE NOTED. CLOSED LT ENG LOWER COWL, C/W DETAILED INSP OF ENG MOUNT POINTS & REAR ENG STRUT SEALS, NO DEFECTS NOTED IAW AMM 71-00-01.