What was found
PILOT REPORTED LT FUEL BOOST PUMP CIRCUIT BREAKER POPPED IN FLIGHT. UPON INSPECTION OF FUEL PUMP IN LT WING ROOT, IT WAS APPARENT THERE HAD BEEN A BRIEF FIRE IN THE AREA. PLASTIC SPIRAL WRAP AROUND FUEL LINE HAD SHRUNK AND MELTED. PNEUMATIC LINE TH LT WING DE-ICE BOOT WAS MELTED. AREA WAS COVERED WITH SOOT. WIRE TO LOW-PRESSURE BOOST PUMP HAD CHAFFED AGAINST THE FUEL LINE TO BOOST PUMP WARNING PRESSURE SWITCH. THE WIRE ARCED A HOLE IN THE FUEL LINE CREATING A FUEL LEAK AND FIRE. WHEN CIRCUIT BREAKER POPPED, BOOST PUMP FAILED AND REMOVED PRESSURE FROM LEAKING LINE.