As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
NUMBER 2 HOC. DUE TO 8 QTS OIL ADDED AND OIL USAGE TRENDING UP PERFORM HOC TROUBLESHOOTING PER MM, BAG & BREATHER CHECK. RUN ENGINE AT 80% N2 FOR 10 MINUTES. REPAIR ANY LEAKS FOUND. IF UNABLE TO RUN AT HIGH-POWER, ACCOMPLISH STATIC LEAK CHECK (GEARBOX PRESSURE CHECK) PER MM. ACCOMPLISHED HOC CHECK. NO LEAKS NOTED. REMOVED FUEL OIL HEAT EXCHANGER ASSY WITH BYPASS VALVE, BUILD UP NEW ASSY IAW. REPLACED FUEL-OIL HEAT EXCHANGER ASSY WITH BYPASS VALVE ASSY IAW MM. RAN ENGINE PER JRH, OP CHK LEAK OKAY.