What was found
(CAN) AFTER OUR AIRCRAFT ARRIVED ON THE PARKING POSITION OUR TECHNICIAN REPORTED SMOKE AND FLAMES COMING OUT OF THE LT ENGINE COWLINGS AND AIR INTAKE SECTION. THE FIRE WAS EXTINGUISHED AND THE CAUSE WAS FOUND TO BE THAT THE AIR INTAKE HEATER CAUGHT FIRE. THE AIR INTAKE WHICH WAS THE CAUSE, WAS A PRE MOD UNIT PN 4100S028-01. RELATED REFERENCE, SYD 84-30-02, APPLIES ADDITIONAL SEALANT TO PREVENT FLUID INGRESS TO HEATER CORE. PN 4100S028-03, POST MODSUM 4-113435