What was found
SMF FLIGHT NR 2307: AT 25,000' SMOKE WARNING LIGHT FOLLOWED IN 1 TO 2 MINUTES BY THE NR 2 ENGINE OIL PRESS WARNING LIGHT. SHUTDOWN THE NR 2 ENGINE. MAINTENACE REMOVED AND REPLACED THE NR 2 ENGINE, NR 2 PROP, (P/N 697070003, S/N DAP0217), NR 2 AC GENERATOR (P/N 28B555-1, S/N 067C0102), AND NR 2 OIL COOLER AND BETA TUBE (P/N D2887-815A, S/N M107329) IAW QX MTC 6710003, 6710004, 6610003, 6610004, 6242101, 6610001, 6610002. OPERATED ECS SYSTEM WITH NR 2 ENGINE BLEED AIR UNTIL NO ODOR WAS NOTED. ALL CHECKS GOOD. NO LEAKS DETECTED. AIRCRAFT RETURNED TO SERVICE.