What was found
DURING A PREFLIGHT INSPECTION, PILOT IDENTIFIED SEEPAGE FROM LT WING QUICK DRAIN. FLUSHING DID NOT REVEAL DEBRIS THAT WOULD HAVE CAUSED LEAK, AND DID NOT ARREST LEAK. QUICK DRAIN INSTALLED 2 YEARS PRIOR DURING FUEL CELL REPLACEMENT. ON DISASSEMBLY, IDENTIFIED THAT THE O-RING WAS SEVERELY DISTRESSED, AND COVERED WITH CRACKS, PROVIDED THE CORRECT O-RINGS AS REPLACEMENTS. REQUESTED TO FILE SDR, SO OWNER FILING SDR TO IDENTIFY THIS ISSUE FOR TRENDING. NOT A FLIGHT SAFETY ISSUE - LEAK WAS MINOR. HOWEVER, IT APPEARS THAT THE WRONG O-RINGS WERE PROVIDED WITH QUICK DRAINS BY OEM. PART NUMBER UNKNOWN.