The Cessna 120-140 Association Forum

Does anyone know which model wing tank drain valve the A models use? I’ve read here that some years had straight thread some years tapered thread. Mine are Curtis valves, just not sure which model.

My 140A utilizes the Safe Air CAV-170 drain valve which is a 7/16 - 20 UNF thread.

Can you see the part number of the Curtis Valve on your tank?

According to the 140A parts book an AN814-4D plug which is a 7/16-20 thread was utilized originally.

Mike, I won’t be with my plane for a week or so. I’ll take a look when I get back. I have the push and twist style Curtis.

The Saf-Air CAV-170 cross references to the Curtis CCA-2100. However that one appears to be a push type and not the push and twist. Maybe they changed the design or I may not have done enough research yet.

I like the ability to replace the o-ring in the Saf-Air. Maybe I’ll switch to that. I wonder if either are considered better than the other?
Josh

If your fitting is drilled for safety wire then it should be straight thread. Pipe threaded drains were typically not.

After inspecting my drain valves, I found that they are Curtis CCA-4300 which is straight thread.

I had one weeping a little and after exercising it a bit of lint came out. I think that was my problem. Seems to be dry now. I like easy fixes!
Josh