What was found
A CT-58 FUEL CONTROL UNIT (FCU) PN 725725-5 SN 29172)) , STATOR VANE ACTUATOR (SVA) PN 4004T63G10 SN KTR4579BR)) , AND PILOT VALVE (PV) PN 6028T23G01 SN KTR3098BR)) WERE DELIVERED BY THE NTSB AND CARRIER FOR INSPECTION. INITIAL DISASSEMBLY OF THE FCU, SVA, AND PV SHOWED CONTAMINATION FROM AN UNKNOWN EXTERNAL SOURCE (WHICH MAY STILL BE PRESENT ON IN-SERVICE AIRCRAFT) AND POSSIBLE CONTAMINATION FROM THE CENTRIFICAL FUEL PURIFIER (WHICH WAS NOT DELIVERED WITH THE UNIT FOR EXAMINATION). DISASSEMBLY OF THE UNIT REVEALED THAT THE MAIN FUEL CONTROL FILTER HAD ALSO BEEN REMOVED PRIOR TO DELIVERY TO CHI HOWEVER THERE WAS ONE SMALL METALLIC NON-MAGNETIC SLIVER OF DEBRIS FOUND IN THE MAIN FUEL CONTROL FILTER HOUSING. OUR INITIAL EVALUATION AND DISASSEMBLY OF THESE UNITS REVELED NO EVIDENCE OF MECHANICAL FAILURE OR IMPROPER ASSEMBLY.