What was found
(CAN) DURING DAILY INSP OF ACFT, FUEL WAS NOTICED COMING OUT OF THE APU ENCLOSURE DRAIN MAST. APU COMPARTMENT WAS ACCESSED TO DETERMINE THE SOURCE OF THE FUEL AND IT WAS NOTED THAT THE ENCLOSURE WAS DAMP WITH FUEL. ENCLOSURE WAS CLEANED OF ALL FUEL AND COMPLETED A GROUND RUN OF APU TO DETERMINE SOURCE. DURING RUN, FUEL FROM THE MANIFOLD CONNECTION TO A SECONDARY NOZZLE WAS SPRAYING FUEL ONTO THE BURNER CAN PRODUCING SMOKE. CLOSER INSP REVEALED THAT THE LINES GOING TO THE SECONDARY NOZZLE WERE LOOSE. CONTACTED MFGS AND BOTH STATED THAT THE FUEL LINES SHOULD NOT HAVE LOOSENED AND RECOMMENDED THAT ALL FUEL NOZZLES (4 SECONDARY AND 2 PRIMARY) ALONG WITH THE MAINFOLD BE REPLACED PRIOR TO REACTIVATION OF APU. THIS IS THE SECOND OCCURANCE OF THE FUEL MANIFOLD LINE LOOSENING OFF THE FUEL NOZZLE ON THIS APU WITHIN THE LAST YEAR.