What was found
RDD - RIGHT ENGINE OIL LIGHT ILLUMINATED IN FLIGHT. CREW SECURED NR 2 ENGINE AND DECLARED AN EMERGENCY. AIRCRAFT LANDED WITHOUT INCIDENT. MX SUSPECTS POSSIBLE INTERNAL LEAKAGE IN FUEL/OIL HEATER. MX REPLACED FUEL/OIL HEATER. OIL QUANTITY AND PRESSURES NORMAL DURING ENGINE GROUND RUN. NO LEAKS DETECTED. AIRCRAFT RELEASED FOR TEST FLIGHT. SUBSEQUENT TEST FLIGHT NORMAL. AIRCRAFT RETURNED TO SERVICE. (M)