Fuel sump takes a dump

iflyvfr

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Beautiful WX this week in Ohio, so Thursday after work I'm going to hangar. I check the right wing sump and then the left. Wait, what's this blue stain and tiny drip? I look on the floor but don't see anything so I take my Gats jar and poke the pin in like I've done a thousand times. Take my sample and then all hell breaks loose: it won't reseal.IMG_2262.jpg Uh oh!

My sample jar is filling quickly as I frantically tried to get the flow of expensive blue stuff to stop. No such luck. But now I know why pilots frequently keep a couple of 5 gallon gas cans and a length of tube in their hangars - fortunately I found one (actually 2) of them to assist! I plugged a length of hose and sat there babysitting for hours as the 15 gallons drained into the cans - slowly. IMG_2263.jpg IMG_2265.jpg

Fortunately, my mechanic returned my phone call and looked up the P/N for me. I confirmed the part on A/C Spruce matched what was stamped on the drain and placed an order - for 2 of them. But I'm grounded until some day next week. IMG_2275.jpg Sure wish I had thought to do that last month during annual.
 
It would likely have stopped if you had tapped it (lightly) with a hammer. BTDT. They will stick like that when they get rusty from water in that sump. You'd still need to replace it.
 
That I didn't try but I stuck everything I could think of in there to get it to reseal. I thought if I removed the drain it would flow faster, and it did but then the hose I had wouldn't stay in place. Fortunately the valve came right out with a turn of a 3/4 "crescent wrench.
 
I had the exact same thing happen on the Husky a couple of weeks ago. It kept trickling after I sumped the tank after re-fuelling. Nothing I did would re-seat it. I think maybe a chunk of hardened O-ring got trapped in it?

Didn't drain the tank though. Stuck a bucket under it and got a foam ear plug (hearing protector). Took out the drain and plugged it until I located a replacement quickdrain at one of the shops on the field. Got that installed with some thread sealant without losing much avgas (eye protection advised).

Going to do the other side the same way, some time when the tanks are lower though.
 
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... I think maybe a chunk of hardened O-ring got trapped in it?
I took a look at my old drain today and that's exactly what happened. There was a small piece of hardened O-ring that had broken off inside and was sticking out where the fuel flows thru. I pushed the plunger up and it fell out in my hand.
 
It would likely have stopped if you had tapped it (lightly) with a hammer. BTDT. They will stick like that when they get rusty from water in that sump. You'd still need to replace it.
When the "O" ring is hard and broken, ain't nothing going to fix it except a new "O" ring.
 
Fortunately the valve came right out with a turn of a 3/4 "crescent wrench.[/QUOTE]
Could you post a picture of that 3/4 inch Crescent wrench, I've got a 4 inch, that's the smallest i've seen, but I'd sure like to see one that size, thanks
 
Fortunately the valve came right out with a turn of a 3/4 "crescent wrench.
Could you post a picture of that 3/4 inch Crescent wrench, I've got a 4 inch, that's the smallest i've seen, but I'd sure like to see one that size, thanks[/QUOTE]

Crescent makes a full line of combination wrenches just like any of the other tool manufacturers such as Craftsman or Snap-on. Amazon sells them if you are looking for one. Click here.
 
When the "O" ring is hard and broken, ain't nothing going to fix it except a new "O" ring.

Yup. I was refering to drain valves stuck because of rust.

In the flight school I replaced all the drain valves yearly with either new valves, or used ones with new O-rings. No ugly surprises that way.
 
Yup. I was refering to drain valves stuck because of rust.

In the flight school I replaced all the drain valves yearly with either new valves, or used ones with new O-rings. No ugly surprises that way.
Did you notice? that is a Cessna. There are no iron parts in a Cessna fuel system.
How would you get rust in a fuel system?
If it is jammed open by debris, why would you put up with that?
 
Did you notice? that is a Cessna. There are no iron parts in a Cessna fuel system.
How would you get rust in a fuel system?
If it is jammed open by debris, why would you put up with that?

Tom, the valve itself is steel (mostly iron) and it corrodes. Some of us have seen that many times.
 
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I'm guessing someone confused "Crescent" with "adjustable". :D

When I was growing up, everyone knew them as Crescent wrenches... You used the word "adjustable" and you would be considered a sissy...

Also, I always wondered why my old flying club airplanes always had golf tees in the glove box. I found out the hard way...
 
I'm guessing someone confused "Crescent" with "adjustable". :D
LOL, I'm not terribly mechanical - does it show? :confused: My A&P said just 'use a crescent wrench' and I had a regular 3/4" wrench that worked just fine to remove and inspect it. I should stick to pictures...wrench.JPG That's also why I will pay him to replace the new ones...
 
Could you post a picture of that 3/4 inch Crescent wrench, I've got a 4 inch, that's the smallest i've seen, but I'd sure like to see one that size, thanks

@SkyDog58 I think what is confusing you is that Crescent originally made a name for itself as a manufacturer of adjustable wrenches. Since then they have diversified into non-adjustable wrenches also sold under brand-name Crescent!

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Tom, the valve itself is steel (mostly iron) and it corrodes. Some of us have seen that many times.
Stick a magnet on it, you'll find it isn't. and the OE doesn't rust, it'll turn black, that's all.

after market might be steel but every one I've seen are cad plated.

Cessna tanks are either a rubber bag or an aluminum tank. all snaps are on the out side of the bag, you'd be hard pressed to see any rust in the Cessna fuel system.
 
@SkyDog58 I think what is confusing you is that Crescent originally made a name for itself as a manufacturer of adjustable wrenches. Since then they have diversified into non-adjustable wrenches also sold under brand-name Crescent!

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Actually, I don't think @SkyDog58 was confused. He was busting the OP about referring to a crescent/adjustable wrench by the opening size instead of the length of the wrench. A 3/4 inch long adjustable wrench sure would be (as my wife would say) "Cute".
 
Stick a magnet on it, you'll find it isn't. and the OE doesn't rust, it'll turn black, that's all.

after market might be steel but every one I've seen are cad plated.

Cessna tanks are either a rubber bag or an aluminum tank. all snaps are on the out side of the bag, you'd be hard pressed to see any rust in the Cessna fuel system.
My C150 got its fuel tank replaced with a used one before I got it. That tank always has a bit of crud in it. Sure looks like rust. Never shows up in the belly drain or gascolator, but it comes out the wing drains and occasionally a piece gets stuck in the drains and I have to flush a little more fuel out.
 
@SkyDog58 I think what is confusing you is that Crescent originally made a name for itself as a manufacturer of adjustable wrenches. Since then they have diversified into non-adjustable wrenches also sold under brand-name Crescent!
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I can assure you that I am not confused. I know the difference between open end, box end, combination, and adjustable wrenches. I also know that Crescent is a manufacturer of various wrenches and other tools, not just adjustable wrenches. I was just poking at @Gary Austin for his questioning of @iflyvfr for mentioning a 3/4” crescent. They do exist. I doubt if he used an adjustable and referred to it by its opening size. To me he obviously used an open end or box end. Now whether it was Crescent brand or not, I do not know. Still, it could have been.

My only error was not correcting how the system handled my quoting of the way @Gary Austin quoted @iflyvfr. I should have cleaned it up as it made it look like I said what Gary said. But if you read each post in sequence and look at the close quote coding, it will be clear what happened. Gary’s stray closed quote messed up my quoting of him.
 
@SkyDog58 I think what is confusing you is that Crescent originally made a name for itself as a manufacturer of adjustable wrenches. Since then they have diversified into non-adjustable wrenches also sold under brand-name Crescent!

1764805.jpg


-Skip
Actually, Crescent refers to the length of the wrench as the size, thus a 3/4" Crescent wrench would fit on your keychain.
 
My C150 got its fuel tank replaced with a used one before I got it. That tank always has a bit of crud in it. Sure looks like rust. Never shows up in the belly drain or gascolator, but it comes out the wing drains and occasionally a piece gets stuck in the drains and I have to flush a little more fuel out.

The filler neck is steel. The OEM drain valve is steel (I worked at a Cessna dealer and am familiar with OEM parts). The fuel level sender has a steel mounting plate, a steel rod, and a steel rheostat cover. Any of this stuff can drop rust into the tank.

It's all cad plated when new, just like AN hardware. And, just as with AN hardware, the cadmium sacrifices itself to protect the steel, and once the cadmium is gone the steel rusts.
 
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