What was found
UPON ARRIVAL AT KCVX, ENGINE NR 2 HUMMING NOISE PRESENT WHILE WIND MILLING W/ NO POWER ON IN AIRCRAFT. ON DEPARTURE, NR 2 ENGINE FAILED TO START FIRST TRY; NOTED N2 ROTATION BUT NO N1 OR FUEL FLOW. ENGINE STARTED ON SECOND ATTEMPT. IMMEDIATELY AFTER DEPARTURE NOTICED AN ABNORMAL MECHANICAL/BURNING SMELL THROUGHOUT CABIN AND COCKPIT. SMELL DISSIPATED AFTER 5 MINUTES. ALL ENGINE AND ELECTRICAL INDICATIONS NORMAL THROUGHOUT FLIGHT. REMOVED AND REPLACED THE NR 2 ENGINE IGNITION EXCITER W/ OVERHAULED ASSY IAW LM/M 74-10-01. ACCOMPLISHED MULTIPLE ENGINE STARTS IAW 71-00-01. OPS CHECK GOOD, NO ODORS. P/N OFF/ON: 500335-1 S/N OFF: NNA10120002 S/N ON: NNA16340112.