A BELL JET-RANGER INCURRED FUEL NOZZLE FLOW PROBS AND COMBUSTION LINER CRACKS DUE TO SUSPECTED FUEL CONTAMINATION.

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ACFT CAME TO SHOP FOR ROUTINE PHASE INSPECTION. NOZZLE INSPECTION WAS DUE. NOTED SEVERAL NOZZLES WITH FLOW PROBS. FURTHER INSPECTION FOUND COMBUSTION LINER WITH SEVERAL CRACKS. NO APPARENT REASON FOR THE ISSUES. FURTHER RESEARCH FOUND THAT THE LIKELY PROB WAS CONTAMINATION OF THE FUEL. SINCE MAR/FRI/02; ALL FUEL SUPPLIED CAME FROM OUR FACILITY; EXCEPT FOR ONE STOP AT ZZZ. ON APR/FRI/02; OUR PLT PICKED UP 120 GALS OF JET A. HE NOTED ON HIS LOG THAT THEIR FUEL TRUCK WAS BROKEN AND THE ACFT WAS MOVED TO THE FUEL FARM AND APPARENTLY FUELED DIRECT FROM THEIR STORAGE TANKS. DURING THE PHASE INSPECTION OF THE ACFT IN QUESTION OUR DE-FUEL CART FILTER PLUGGED. FURTHER RESEARCH FOUND CONTAMINATION TO BE THE CAUSE. WE THEN BEGAN THE PROCESS OF 'WHERE DID THE CONTAMINATED FUEL LIKELY COME FROM?' NOT LONG INTO THE PROCESS THE FLT LOG WITH THE NOTE REFING THE FUEL TRUCK PROB WAS FOUND. AT THAT POINT THE FUEL CONTAMINATION ISSUE TOOK ON A MORE CREDIBLE LOOK. COMPONENTS IN QUESTION WERE SENT FOR EVALUATION. MR X HAS INSPECTED THE HOT SECTION OF ENG AND HAS NOT FOUND ANY FURTHER DAMAGE AT THIS TIME. ALTHOUGH THIS PROB APPEARS TO HAVE BEEN INITIATED ON APR/FRI/02; WE HAD NO REASON TO SUSPECT A PROB UNTIL THE NOZZLE CLEANING OCCURRED. FUEL CTL AND FUEL PUMP WILL BE REMOVED FOR EVALUATION.