You all sump fuel? Also, what is this!!??? (Not clickbait)

Do you sump your fuel tanks?

  • Yes, before every flight

    Votes: 39 36.4%

  • Yes, before first flight of the day

    Votes: 65 60.7%

  • No way.

    Votes: 3 2.8%
  • Total voters
    107
Gilbert Buettner said:
Sumping immediately after refueling probably isn't going to reveal much, since water would likely be in suspension for some time. Give it 15 minutes instead of 15 seconds, in my opinion.
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You ordered 20 gallon of fuel and was delivered 20 gallons of water. It is going to show up.
 
luvflyin said:
Every flight because I preflight every flight. Sometimes it’s obviously not really necessary but I will not break my routine.
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Same. I know Emerson called it the hobgoblin of little minds, but me and my little mind try really hard to do the same procedures, every single time.
 
Gilbert Buettner said:
Sumping immediately after refueling probably isn't going to reveal much, since water would likely be in suspension for some time. Give it 15 minutes instead of 15 seconds, in my opinion.
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I like to fuel the plane, go pee, check the freezer for ice cream bars, and then sump the tanks.
 
TCABM said:
Community hangared and yes, I sump before my first flight of the day and after every refuel.
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Of course, sumping right after a refueling can lead to a false sense of security. I believe it was our own Ron Wanttaja who had a ILAFFT article on the subject decades ago in Flying.
 
Sump after fueling and before first flight of the day.
 
Stewartb said:
Private hangar parked, fueled from my own secure tank. I sump and check oil level before every flight.
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Oh, but not in winter when parked outside or otherwise cold soaked. Can’t sump ice and trying jams quick drains. For winter I use isopropyl.
 
Just spitballin', please feel free to tell me how I am wrong. Is there any way that since the contaminants were only in the mains, that it was coming from one of the fuel pump return lines?


Edit: Understand that that would be very unlikely in this case, but just wondering if a leaking engine fuel pump could drive crank case vapor and oil back into a fuel tank via a return line.
 
dans2992 said:
I’ve observed different outlooks on sumping Jet A burners vs pistons…
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I’ve sumped a Jet 6 hours after fueling, and it showed up clean. We made a precautionary landing due to fuel issues that evening, and the next morning we got about half a quart of rusty water out of the tank that turned out to be the center of our problems. It had affected both gauging and transfer after takeoff.
 
Any difference in risk of water between fuel truck and fixed tanks?
 
MauleSkinner said:
the next morning we got about half a quart of rusty water out of the tank that turned out to be the center of our problems.
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Turbine fuel has a strange way of holding water sometimes. Due to that, after a couple high profile fuel issues, the old 135 day job required a fuel sample taken for every aircraft as part of the mechanics after-flight (daily) inspection complete with detector paste. The next morning, before 1st flight the pilot was required to check that sample plus check a 2nd pre-flight sample.

Ed Haywood said:
Any difference in risk of water between fuel truck and fixed tanks?
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The risk is more in who is managing the fuel system and under what guidelines.
 
I live at an airpark, so my plane is in the hangar right next to our house. The hangar is locked at night, is as watertight as the house, and has a dehumidifier. I still visually check the tanks and drain the sumps before the first flight of the day. It only adds a few seconds to preflight. I also drain samples after refueling.
 
Gilbert Buettner said:
Sumping immediately after refueling probably isn't going to reveal much, since water would likely be in suspension for some time. Give it 15 minutes instead of 15 seconds, in my opinion.
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Take a water bottle with 1/4 water left. Sump tanks. Shake.

It ain't in suspension by the time I'm done rolling the hose up.
 
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eman1200 said:
I've told this story before......rented a cherokee years ago....plane was out with an instructor/student....they came back, parked the plane and went inside for debrief. I started preflighting and when I got to sumpin' I said sumpin' aint right with this fuel.....it was 90% water......kept sumpin and sumpin. instructor walked by me and I showed him how much water was there....he said "I personally watched the student sump and there was no water"....I said well there's water now lol. he was shocked. I was shocked. kept sumpin and sumpin til there was no more water. but mine was clear water, not sploogy lookin stuff like kaiser got. this plane was always parked outside.
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Was that both tanks? Don’t seem like the plane could have been flying with that much water if that’s the side they were on
 
luvflyin said:
Was that both tanks? Don’t seem like the plane could have been flying with that much water if that’s the side they were on
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It was a long long time ago but I ‘think’ it was only on one side. Don’t quote me though.
 
Here's an interesting test where they poured 64 ounces of water (half a gallon) into a 152 fuel tank and the water never reached the sump drain.

Cessna Tank--Sump and Sump Drain Test

Test performed to determine if tank's sump drain is located at tank's sump.
www.sumpthis.com

I know there is a video on youtube about another sump issue but I can't seem to find it.

Bottom line is that few ounces you are draining is almost never gonna tell you if you have water in the tanks, only that you have SO MUCH WATER that it actually made it to the sump drain to actually be detected.
 
Before every flight - no exceptions. Only gotten water once in 9 years with my plane. Refueled in the rain. Simple and quick, then no worries or guessing. Used to get water often in the 90’s with flight school planes - rare now.
 
The only real amount of water found after sumping was during a pre-flight conducted on a plane I was considering purchasing, just before going flying, and kept under a shade hanger in Las Vegas. The owner said don't bother, it doesn't rain much here. Sumped it anyway and on one side discovered almost a full tube of scuzzy water (looked just like the OP's 2nd photo).
 
Salty said:
Beware of bladders too. I was able to get water out of a Cessna with bladders just by rocking the plane for a few minutes. Took a dozen attempts before I didn’t get any.
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That should be standard practice with nitrile bladders. But, if you’re the sole pilot? Flying and taxiing accomplishes it for you. If in doubt, sump post-flight and again at next pre-flight. Learn the tendencies of your plane.
 
I mostly fly PA-28s, and I sump before every flight. I have found water in the tanks, aircraft stored outside, more than once.

I also start on one tank, then switch to the other for taxi, run up, take-off. Partly that's for water, but just to be sure I have feed working from both tanks and a selector set right.
 
In the 8 years of sumping my fuel tanks I have only found one drop of water one time. Our airport keeps a close eye on the fuel tanks. Buy most of my fuel at home.
I keep it in a hangar, not often does it get rained on.
One of the first things I did right after I bought the plane was to put 2 new fuel cap gaskets on it. They still fit snug.

I am in the fuel business. 55 gallon drums with the bungs sealed really tight can still pull water into a drum through the bung gaskets. Especally if the drum is warm and cool rain puddles on top of it, it suck the water into the drum through the gaskets because the drum develops a suction when it is cooling down. So always keep a rock or block of wood under the drum if outside so the water won't pool on the bung openings.
I think the same thing can happen to a aircraft if it is warm and cool rain comes down especially if the venting is partially blocked.
 
Preflight, always.

Enroute, my wife and I have a set procedure, I specify how much I want, usually full.
I go close the flight plan, get briefed for next leg, and file new plan, and go to the bathroom.
Wife pays for the gas, and oil if added, and goes to the bathroom.
I shake the wings to settle water at the sump, do a complete preflight, including checking caps on correctly, sumping tanks and gascolater (Most important sump).
Wife returns to plane, we compare expected fuel burn to actual purchase, and we are ready to go.

We were a good team, she took the commercial ground school with me, and passed the final exam with a higher score than many of the pilots in the course. She has flown more than 800 hours of cross country with me.

All the planes that I have flown were tied down outside, and small quantities of water was common, especially after a violent thunderstorm.
 
eman1200 said:
"I personally watched the student sump and there was no water"....I said well there's water now
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By any chance do you know if the plane was parked on a slant, even a SLIGHT slant, before "...the student..." sumped the tank the first time and the wing with the water was a bit low? Same (opposite) possibility with wings that have two cells and when you sumped that wing was in on a slant with the wing high OR the planes motion during flight forced some trapped water in the other cell to finally come down to the drain. There are some possibilities that can cause water to get stuck and then show up after a flight.

Somewhere over the years someone taught me that when I first walked up to the plane to put my hip up against the wing (or grab the strut on a Cessna) and give the whole plane a good shake. By the time I've finished organizing and doing the cockpit check, any water that may have broken free from the second cell should have made its way down to the drain and you'd see it when you sumped the tank. Of course, this does nothing if the plane is parked with one of the wingtips lower than or even equal too the drain.
 
Gary Ward said:
In the 8 years of sumping my fuel tanks I have only found one drop of water one time. Our airport keeps a close eye on the fuel tanks. Buy most of my fuel at home.
I keep it in a hangar, not often does it get rained on.
One of the first things I did right after I bought the plane was to put 2 new fuel cap gaskets on it. They still fit snug.

I am in the fuel business. 55 gallon drums with the bungs sealed really tight can still pull water into a drum through the bung gaskets. Especally if the drum is warm and cool rain puddles on top of it, it suck the water into the drum through the gaskets because the drum develops a suction when it is cooling down. So always keep a rock or block of wood under the drum if outside so the water won't pool on the bung openings.
I think the same thing can happen to a aircraft if it is warm and cool rain comes down especially if the venting is partially blocked.
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Condensation is a bigger threat than rain. I've always been told to fill the tanks after the last flight to reduce the condensation generated. GA fuel tanks are vented, so there is always a temp differential and an ingress for moisture to enter.

Also, many sump drains are not in the actual tank sump, leaving water. Just because you don't get water in your 2 oz of fuel sample doesn't mean there's no water in the sump.
 
Sumping my hangared plane I pour it into a 1 gallon gas can. That fuel is perfect for pouring into my chain saw and back pack blower over the winter. Don’t need no Stabil or SeaFoam.

On the ramp, it’s oddly satisfying to fling 100LL out of my little sumping tool.
 
455 Bravo Uniform said:
Sumping my hangared plane I pour it into a 1 gallon gas can. That fuel is perfect for pouring into my chain saw and back pack blower over the winter.
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No lead fouling? I was considering avgas for a 2-stroke application, just wasn't sure they'd clear the lead properly.
 
AV8R_87 said:
No lead fouling? I was considering avgas for a 2-stroke application, just wasn't sure they'd clear the lead properly.
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I don’t run it all the time, just fill the tank for winter storage and run it for a few minutes to clear the regular gas line out. And then start in the spring for normal use. A tank per year hasn’t hurt that I can tell. A disappointment is that it doesn’t smell as good as when it’s burned in an airplane.
 
I’ve run a lot of hours on 2-strokes with 100LL. No problems but no advantage. Small, fuel efficient 4-strokes are a different story. Honda power equipment does not run well on 100LL.

I have an old 5 gallon bucket with an oil absorber pad that I leave at my fuel shed. I dump sumped gas into that and let it evaporate. No avgas gets tossed on my ramp, but I own that asphalt!
 
I sumped before every flight and after every fuel stop during training. I never found water and the plane was hangared, but it seemed like a good habit to build. My first flight post-PPL was at an airport in FL, and I sumped as per usual. I filled two whole jars plus half of another with water before avgas started coming on, just from one side. The other side had about half a jar water, half avgas on the first try. I gave the plane a good shake for a few minutes/sloshed the fuel around and then finished my preflight, at which point I sumped again. No more water came out and the flight went fine, but that experience definitely cemented my resolve to always sump before every flight. That plane had already flown that day, too.
 
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