As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF, THE FLIGHT ATTENDANTS REPORTED A BAD MUSTY - MILDEW ODOR THROUGHOUT THE AIRCRAFT. DISSIPATED AS AIRCRAFT MADE IT TO ALTITUDE. THEN AGAIN DURING DESCENT. THE AIRCRAFT WAS GROUNDED. REPLACED THE STARTER AND CLUTCH SEALS AND O-RINGS IAW AMM 49-42-55.