SEAL KIT, Fuel Drain Valve

Curtis Superior and SAF-AIR valves are designed for installation in a standard NPT port for NPT threaded valves or an AND-10050 style port for UNF threaded valves. Use a thread sealant or Teflon tape on pipe threaded valves. Never allow any thread sealant on the first thread . This will prevent contamination of the fuel system. Refer to aircraft manufacturer's torque specifications for the aircraft in which it is being used.

Replace the rubber seals as per the aircraft manufacturer’s recommendations or every ten years when no guidance is given. McFarlane stocks replacement seals and seal kits for both Curtis Superior and SAF-AIR valves. The new Curtis valves use a O-ring type seal instead of the flat seal that was previously used. 

SAF-AIR valves are designed to be disassembled and the O-rings replaced. Over time, if the valve should start to leak, check to make sure the drain valve is tight. If drain valve is found to be tight, then check the O-rings. All O-rings used are buna "n", MS29513 Style, MIL-P-5315. SAF-AIR O-ring seal kits are available for most of their valves. Add a "K" or "-K" suffix to the valve part number.

Never have a hose attached in flight to the oil drain valve. Engine vibration and the additional attached mass can cause premature seal and valve wear which could result in valve failure and a loss of engine oil.

The fuel selector valve works in unscreened fuel. Contaminated fuel can cause selector valve seal damage. When fueling from possibly contaminated fuel sources McFarlane recommends the use of a fuel filter, such as Mr. Funnel or another filtering device, to reduce trash in the fuel system.