The International Cessna 170 Association

I have a Koehler K9500A-1 drain valve. It has a tab that is spring loaded and turns 90 degrees to open. Anyone know if its a common o-ring or a special seal like curtis uses.
Thanks

I have the same valve and am looking for replacement o-rings. Does anyone have any information on what o-rings this valve uses. It looks like there are two o-rings.

I do not know about the rubber "O" rings but want to add a cautionary note about the cork gasket sealing the glass bowl to gascolator Body.

Be careful ; It is possible for the gasket to crack , allowing air to act like an embolism. Fuel will not flow to carburetor.

There is an AD for this on a non Cessna aircraft.

These Curtis Drain valves (PN CCA-7450) are available at Spruce, McFarlane, etc. and are inexpensive. The instructions for these valves state: "Curtis Superior Valves cannot be OVERHAULED. Replace the entire valve per the maintenance schedule of the aircraft in which it is used or usable life per Curtis Superior Valve should it begin to leak. "
$16.50 at Spruce: https://www.aircraftspruce.com/catalog/ ... DMQAvD_BwE

I will not use Curtis valves on my aircraft as they provide catch and snag problem. Having them under the wing ,well they hit my head many times and inferred with the door opening and closing . The solution is using SAF valves and I use SA-14 valves every where . While not perfect ,the small circlip in the end of the valve pops out rendering the valve open. But carry a couple of spares .
Plus Curtis valves in my country cost nearly $70 each . The SAF valves cost me around $50 here.

Whew, that's some thread creep!

Mike, I've never taken my K9500A-1 valve apart so I don't know for sure, but I'd guess it uses an O-ring. Have you disassembled it? It would help the rest of us to know.

DaveF wrote:Whew, that's some thread creep!

Mike, I've never taken my K9500A-1 valve apart so I don't know for sure, but I'd guess it uses an O-ring. Have you disassembled it? It would help the rest of us to know.

That's probably my bad.... I forgot Mike Roe has a ragwing and looked up the drain for a B-model (which uses a Curtis.) Often times drain valves have been repaired using common nitrile O-rings which are not actually the correct part because the seal is shaped slightly-differently than an O-ring cross-section. If a common O-ring is substituted for the approved seal it carries the liability that it may dislodge during operation and fail to re-seat properly leading to fuel-loss/fire-hazards. Just FYI.