IMPORTANT VALVE INSTRUCTIONS:
Curtis Superior Valves do not use O-rings, they use a special flat molded seal, therefore can not be overhauled. If the valve is leaking, clean the seal area and recheck for leakage. If the valve continues to leak, replace the entire valve per the aircraft maintenance schedule. Curtis valves have a life expectancy of 10 years under normal operating conditions.
Fuel and Oil Drain Specs