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Fuel Tank Quickdrain: Repair or Replace

odens_14

Well Known Member
after almost 10 years, one of my quickdrains on the tank has developed a slow leak that I need to address. I see Van's sells both a full replacement and just the o-ring. My question is the o-ring likely the only issue and replacing that will likely give me another ~10 years or am I just better off replacing the whole thing?

whatever I do I'll do to both sides, so it's likely saving only around $30 to just do the rings but I'd rather spend that on avgas if full replacement doesn't gain me anything.
 
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There’s little that can go wrong with them except the O-rings. I have spares on hand so if I have a leaky, I replace it, then change the O-ring on the “bad” one and put it back in the spares drawer for the next time.

No, it doesn’t happen on the same airplane vey often - I just have a lot of planes to maintain.....;)

Paul
 
Repair it with a new O ring and put in your travel tool bag. Buy a new one, they’re cheap to put on the plane. That’s what I did.
I also carry a spare filler cap with me as well you never know.
 
Both - Repair and Replace

Order a new quick drain and a few o-rings from Van's.
Install the new drain, then repair the old drain and replace it in the other wing. Then repair that quick drain and keep it as a spare. I carry the spare in the airplane.

Cheers, David
RV-6A - A&P
 
Like others said.

Plus: There is no need at all to drain the tank to swap the quick drain. Unscrew to the last couple of threads, then quickly remove, place a finger over the hole and either thread your spare in quickly, OR have your spouse just hold her finger there while you swap out the o-ring :). "It will just take a couple seconds" might work for you...
 
Thanks guys! that's a good idea to buy one replacement so I can throw one in the tool bag. it will also make the quick switch easier having one all ready to go. I'll order 1 replacement and a few extra o-rings.
 
Thanks guys! that's a good idea to buy one replacement so I can throw one in the tool bag. it will also make the quick switch easier having one all ready to go. I'll order 1 replacement and a few extra o-rings.

Since you are ordering now, another good spare part is the pin/repair kit for the gas cap. Those can also break and leave you stranded. That is another recommended item that is nice to have in the spare/repair kit.
 
Since you are ordering now, another good spare part is the pin/repair kit for the gas cap. Those can also break and leave you stranded. That is another recommended item that is nice to have in the spare/repair kit.

Buy an entirely new gas cap, not just the repair kit. That way, if a cap comes off in flight, you have a spare.
 
Like others said.

Plus: There is no need at all to drain the tank to swap the quick drain. Unscrew to the last couple of threads, then quickly remove, place a finger over the hole and either thread your spare in quickly, OR have your spouse just hold her finger there while you swap out the o-ring :). "It will just take a couple seconds" might work for you...

Exactly what I did and it works great. Just get everything laid out and within easy reach. (I put fuel lube on my quick drains before I started.)
 
Like others said.

Plus: There is no need at all to drain the tank to swap the quick drain. Unscrew to the last couple of threads, then quickly remove, place a finger over the hole and either thread your spare in quickly, OR have your spouse just hold her finger there while you swap out the o-ring :). "It will just take a couple seconds" might work for you...

Stand beside the leading edge and reach under the wing to the drain valve instead of getting under the wing and reaching up to the valve. This will prevent fuel from running down your arm and letting you wear "Oduer de 100LL" the rest of the day. :)
 
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Cool tip? use your cleco pliers to hold the drain valve open while you swap out the o-ring.

I typically use a 1" finishing nail. It is about 1/16" in diameter, fits through the holes and allows all the time one needs to swap o-rings.
 
If carrying a spare quick drain in your fly-away kit, be sure to also include a little ziplock baggie (or similar small container) of your NPT pipe thread sealant to apply to the threads of that quick drain before you thread it into the tank.

I've found a little ziplock baggie works fine - lots of things we buy these days come with a tiny bag of parts - these little bags are just the trick for a tenth of an ounce of thread sealant.
 
Stand beside the leading edge and reach under the wing to the drain valve instead of getting under the wing and reaching up to the valve. This will prevent fuel from running down your arm and letting you wear "Oduer de 100LL" the rest of the day. :)

Indeed! Common sense comes fast to some, not so much for those that just watch their elbow drip blue liquid :).

I think I've stopped at least a half dozen people from draining a whole tank just to swap an o-ring. "But I have to drain the tank in order to...."

This is a great thread.
 
My question is the o-ring likely the only issue and replacing that will likely give me another ~10 years or am I just better off replacing the whole thing?

I would vote for the whole thing. Take a closer look at the drains. If you fly a lot you exercise them very often. I replaced mine after 7 years they rusted away and stems were too wobbly. I burn a fair amount of ethanol laced gas. Get a pack of O-rings and replace them every condition inspection they are super cheap. If you carry a spare you will never need it :)
 
As others have said...buy a new one and replace the o-ring in the old one for a spare.

When changing the drain keep the filler cap on and plug the air vent. You will have very little fuel run out of the drain hole as you change the drain with the vent plugged.

Tie a rag around each wrist. Loosen the drain and quickly put your thumb over the hole as you pull the drain out. Remove your thumb and quickly install the new drain. Remove the tape or rubber cap or whatever you used to plug the vent. Remove rags from wrists.
 
One more tip

I bought three replacement O-rings and changed them all.

My thinking was that if they were old enough for one to start leaking, the other isn't far behind.

Kind of like changing head lights, I replace them in pairs as I have learned that if one burns out, the other isn't far behind.
 
Indeed! Common sense comes fast to some, not so much for those that just watch their elbow drip blue liquid :).

I think I've stopped at least a half dozen people from draining a whole tank just to swap an o-ring. "But I have to drain the tank in order to...."

This is a great thread.


Side note/thread drift.....sort of. I change out water heater elements without draining the tank. Just shut off the water, bleed off the pressure then make sure all the faucets are off. Have the new element at the ready. Jerk the old one and shove the new one in. I may loose a tablespoon of water. If the tank can't get air, it's like trying to pour gas out of can with no vent.:)
 
For those who object to the risks or having hazmat running down their arms:

I fabricated a long hose with fittings and a ball valve. I disconnect the fuel inlet to my injector servo and connect it to the hose. I then select the tank I want to empty and turn on the electric fuel pump.

I pump all the fuel from the selected tank into the other tank. Now I have fewer concerns about removing the drain plug.

Works both ways, of course. Also useful for fuel flow calibration or if you should ever have a fuel tank leak. I used an old air line from my compressor as a hose, but it's not STC'd.

V
 
I've found a pair of Habba Fright rubber gloves (in the flight kit along with the spare valve) and standing in front of the leading edge will keep hands and arms dry. Total loss of fuel is a couple of ounces or so and the entire swap-out takes less than a minute. Your tanks get sumped at the same time! :)
 
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