What was found
ODOR OF BURNING RUBBER IN CABIN AND FLIGHT DECK REPORTED INITIALLY AT 12K BY F/A. NO SMOKE OBSERVED AT ANY TIME. RAN A/C ENGINES IAW 71-00-00. ALL SYSTEMS OPS CHECK GOOD. NO UNUSUAL ODORS, NO DEFECTS NOTED. COMPLETED OPS CHECK OF LT AND RT ACM'S WITH NO BURNING ODOR NOTED. OPS CHECK GOOD IAW AMM 21-10-00. CHANGED RT ACM OIL IAW 21-50-02/25 ACM OIL DARK IN COLOR. CHANGED LT ACM SUMP OIL IAW 21-50-02/25 ACM OIL DARK IN COLOR. CLEANED PASSENGER COMPARTMENT RECIRCULATION FILTER IAW 21-22-02.