As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SEA - JUST AFTER TAKEOFF, BURNED RUBBER/INSULATION SMELL WAS NOTED IN COCKPIT. REOCCURRED DURING BEGINNING OF DESCENT. REPLACED LEFT COOLING TURBINE ASSY AND BOTH LEFT AND RIGHT COALESCER. PERFORMED AIR QUALITY CHECK AND NO ODOR WAS EVIDENT. (M)