I seem to have a never-ending problem with the fuel quick drain valves.

Since completing my plane a year-and-a-half ago I have flush the tanks repeatedly.

I have removed and replaced the quick drain valves so many times its getting a little ridiculous.

Sometimes it's just one stuck piece of metal other times it doesn't seem to be anything at all that causes them to leak. I can't help thinking there's got to be a better fuel drain design and use Curtis valves.

It just makes no sense to me that's something so critical like a drain in the bottom of the fuel tank leaks over and over again.

I'm hoping there's another manufacturer or different design drain other than these Curtis ones. Does anyone have any ideas?



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I feel your pain.  Even wrote an article about it a while back:  http://www.eaa25.org/wp-content/uploads/2015/05/OnFinal201505.pdf

Bottom line:  When I sump my tanks, I always have a spare Curtis Valve + wrench + sealant in hand.  And after sumping, I always go back and check for slow seepage with a piece of paper towel.

Patrick Hoyt


Unlike some things we complain about, this does seem like a real problem in need of a solution - especially for homebuilt aircraft.

Gary -

I had the same issue, scared me every time I had to sump the tank. Had problems with both the of the Zen supplied valves. I got this one from ACS and fixed the issue. THe o-ring is more protected and stays cleaner (I think). Feel like an idiot paying over $20 for it, but it works.

I'm going to order one and try it out. I'm just so sick of dealing with this same problem over and over again. I just don't have the time or patience for it.

thanks for the suggestion! 

Never had that problem, until today! Guess I will be ordering one myself.  I had a ball today flying my 601. Really windy, but once in the air it was great. Most my time has been in the pattern so to just o was exciting. Still learning how to fly my plane. I have never used a gps in a plane, old VOR pilot, so am getting used to them . Made it to 4 different airports and back home.

Is this the standard Zenith NPT thread 1/8"? I want to order two of them, but want to make sure I get the right ones



The CCA-2500 part number is the 1/8 NPT that you want.

Thanks Brad, ordered 2 + the cup


Doesn't look like the better part of a fifty dollar bill, but it is! Now my valves have quit seeping. sort of like the leaky roof when it isn't raining I guess. Sure dread draining my tanks.  O rings or permatex for sealing threads?

Hey Gil 

on this design is the o-ring at the top of the valve and the drain openings near the bottom? I'm trying to understand the difference in the valves.

Gosh Gary I don't really know. I will look at it closer when I go back out to the hangar. I was waiting to burn some gas out of the tanks before I change them out, but I will check and post


Gary I took a good look at my new fuel drains today and what it seams to me is just a top spring pushing down on a plunger with a seal at the bottom. You really cant see anything other that what it appears to be. The top section of the barrel is swaged around the top holding everything in place so I would just assume everything is placed in the barrel, compressed and then swaged. It is a powerful spring so I would think it should have a good seal. The fuel level is picked up maybe a 1/4" above the bottom of the tank I'm guessing. 


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