As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RT ENGINE FUEL FILTER CONTAMINATED WITH LINT FROM LARGE (12" X 30") TOWEL WHICH WAS FOUND IN THE RT INTEGRAL WING TANK. THE TOWEL WAS "INSTALLED" BY CESSNA AIRCRAFT FACTORY WHEN THE AIRCRAFT WAS BUILT. THE TOWEL WAS OUTBOARD OF THE BOOST AND EJECTOR PUMPS AND DID NOT AFFECT THE OPERATION OF ENGINE OR PUMPS.