The Curtis valve fuel drains from Aircraft Spruce were about $10 each
including shipping, they are TSO'ed and come with some kind of sealant at
the base of the thread grooves. They also still have 'O' rings, but the
manufacturer says to replace the
entire valve and not to 'overhaul' the
valve. They were very easy to replace with a 7/16 inch wrench (on the
Archer.)

The Curtis valve does not use an O'ring. At least it is not a traditional
circular cross section O'ring. The cross section of the Curtis seal is more
flat or oval shaped. Many people use standard O'rings to replace this seal and
they will fail sooner rather than later. It is difficult to find the proper
number in a typical aircraft parts book and many people never knew about the
difference in the design of the seals.

Some years ago Curtis stopped selling replacement seals preferring to sell
entire drains instead. Apparently they think this is better than educating the
flying and maintaining public about the use of the proper seal. So instead of
spending pennies to reseal a drain now you have to spend $10.

I would like to know if anyone else sells a suitable seal of the appropriate
style for use on the Curtis drain?

John Dupre'