How often do you sump water?

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AA5Bman

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He who ironically no longer flies an AA5B
I sump before every flight and for all my years of aviation - at least, up until now - I have never had anything larger than a fleck or two of gunk in the cup.

However, my recent plane seems to produce water. Not much, but quite commonly I’ll get a drop or two swirling around in the bottom of the cup, easily cleared by an extra sump or two. I don’t know what to make if it or where it comes from - I live in a dry, desert environment and the plane lives in a hangar. I don’t get it, and I don’t know how concerned to be. The engine never stumbles or suggests it’s ingesting water, and I’ve never gotten much more than a couple drops.

What to do? Do you get any water?
 
I found water for the first time last summer after flying for over a decade... plane was parked outside overnight and rain came through. I replaced my fuel cap gaskets and it hasn't happened again, but my plane is usually hangared and I don't think I've had it out in the rain since.

Anyway when this happened I probably drained about a cup of water from the one tank, then sumped/dumped several samples that didn't have water just to be sure. Flew home. I think for 1-2 more preflights I still would see a drop or two in the bottom of the fuel sampler. I assume some of the water ended up behind baffling or somewhere it didn't get to the sump point until it got flown a few times and worked it's way down as the plane wasn't anywhere it could have been exposed to water inbetween.

So my guess is either you got water from a one off event and you're still finding the remnants or your fuel source could be contaminated. Only other thing would be water coming from somewhere unusual, any pipes/AC drains that could potentially drip in the hangar?
 
AA5Bman said:
However, my recent plane seems to produce water.
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Has this happened since the day you got this recent aircraft, or was there a specific point afterwards from that day?
Wet cell or bladders?
All sumps or just one?
 
I sump every flight. Even with the plane in a hangar I still do it. I also added holding the strainer next to my white cowl and smell it too.

It’s been awhile, but I have found water from a rental after an overnight rain storm.
 
Tools said:

SumpThis, General Aviation

Researching Positive Detection of Water Contaminated Fuel
www.sumpthis.com

Sumped ZERO water right before the flight that put me in a farmers field, due to water.
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Yeah, this is the scary part. One of my CFIs ended up in a field in the same sequence of events. It would be nice to be able to better understand how water seems to find hiding places.

I've personally never sumped water, but was convinced that the effort to keep checking was worth it when my buddy came back to the plane and randomly pulled about half a gallon of water out of one of his tanks. That's how he discovered a newly broken seal on his gas cap.
 
Maybe 3 times in ~1000 hours. Once the first time I flew the club plane on my first flight lesson (how's that for primacy?). Once the first time I flew my plane after buying it, and once after my plane set out in a pretty severe Oshkosh storm. It got a lot less water in it than my tent ;). It sounds like you might have a contaminated fuel source. Also possible if it's a new to you plane, that the previous owner just never sumped and water that has been built up over years is finding its way out. How long has this been going on?
 
iamtheari said:
I think the OP is asking how often you get water from the sump, not how often you check the sump for water. Hopefully that’s not the question that some responses were answering. :)
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Someone less polite would've said something snarky about reading comprehension. I admire your restraint.
 
I used to see water all the time in my T-Craft that was tied down outside. Never seen anything in the hangared planes I've owned since.
 
Plane has always been hangared, and I found water one time. Was obviously from the fuel truck, and notified the FBO right away.
 
The only time I sumped water was during my checkride right after the examiner asked what I would do if I found water.

I had washed the plane a few nights prior and that's how I found out the early pa28's have a different size fuel cap gasket despite being the same part number.
 
For those of you that have sumped significant water, were you able to clear it in a single sumping “session”? Or did it continue to come out in drips and drabs over the next X number of flights? (The later being the “water stuck behind baffles or folds in the bladders” theory). I wonder, because mine is a drip or two every few flights or so, and can’t tell if its the remnant of a single water event or continued intrusion.

Or maybe it’s not even water? I don’t get a “layer” of water with an obvious line of separation. I get what literally looks like a drop of water rolling around in the bottom of the tank. Don’t know what else it could be, but worth mentioning.
 
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Getting water is rare, but it has happened to me as well.
AA5Bman said:
I get what literally looks like a drop of water rolling around in the bottom of the tank. Don’t know what element it could be, but worth mentioning.
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Probably still water.


As others noted, given the thread's original scenario, chances are good it is from the fuel supply. Consider getting fuel from a different source and see what happens.

Might also reach out to the current fuel supplier with a head's-up and then follow-up after results from switching sources.

The one time when I did get a notable amount of water, there was enough to completely fill the cup with all water and no fuel. Interestingly, the water was blue so I was very confused when the specific gravity ball floated. A couple more drains and the cup returned to only fuel. That plane sat on the ramp and got new filler gaskets. Problem solved in that case.
 
AA5Bman said:
For those of you that have stumped significant water, were you able to clear it in a single dumping “session”? Or did it continue to come out in drips and drabs over the next X number of flights? (The later being the “water stuck behind baffles or folds in the bladders” theory). I wonder, because mine is a drip or two every few flights or so, and can’t tell if its the remnant of a single water event or continued intrusion.

Or maybe it’s not even water? I don’t get a “layer” of water with an obvious line of separation. I get what literally looks like a drop of water rolling around in the bottom of the tank. Don’t know what element it could be, but worth mentioning.
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I've typically seen water appearing as little balls or blobs rolling around at the bottom of the cup. In the 150 I've been flying, the left tank seems to always have a little water - but curiously none from the right tank (and they're filled from the same source). Don't understand why. The plane is always hangared, never (as long as I've been flying it) left out in the rain.
 
AA5Bman said:
For those of you that have stumped significant water, were you able to clear it in a single dumping “session”? Or did it continue to come out in drips and drabs over the next X number of flights? (The later being the “water stuck behind baffles or folds in the bladders” theory). I wonder, because mine is a drip or two every few flights or so, and can’t tell if its the remnant of a single water event or continued intrusion.

Or maybe it’s not even water? I don’t get a “layer” of water with an obvious line of separation. I get what literally looks like a drop of water rolling around in the bottom of the tank. Don’t know what element it could be, but worth mentioning.
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On that club Archer, the first time was a bunch, like half of the sample vial. I flew the next day and got a couple BB sized droplets like you're describing. Never saw any again after that. The water I found in my plane after the storm was also just a few small droplets in the bottom of the sampler.
 
Pipers sump easily. Cessnas not so much. Others vary….

The gascolator is KEY to understanding the problem, and the ones that dump (activation not very close to the exit point) onto nosewheel are worrisome. I find a way to collect and check.
 
midlifeflyer said:
I once emptied 4 GATT jars full of water before getting any fuel at all from a Cessna 172. Turned out to be a (very) bad fuel cap seal combined with a heavy rainstorm.
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I was getting some water from the left wing when we first got the plane, especially after a rain. Had the A&P replace the fuel cap seals, and problem went away.
 
I have never found water in 32 years of flying.

I still sump during every preflight. I try to sump after every refuel, but I have to fly to another field and my track record is about 50/50 on remembering the sump cup.
 
Ed Haywood said:
I have never found water in 32 years of flying.

I still sump during every preflight. I try to sump after every refuel, but I have to fly to another field and my track record is about 50/50 on remembering the sump cup.
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Any water will form beads on hard ground and fuel won’t. Typically I just use my fingers to dribble some gas from just the tank sumps after refueling onto the hard ground. Fuel added to just the mains will never have had the opportunity to circulate until you start a pump or the engine.
 
I re
Tools said:
Pipers sump easily. Cessnas not so much. Others vary….

The gascolator is KEY to understanding the problem, and the ones that dump (activation not very close to the exit point) onto nosewheel are worrisome. I find a way to collect and check
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I replaced the stock gascolator in my 175 with a Steve’s gascolator. It doesn’t have the cable-activated dump valve, so you have to reach up inside a bit, but none of it gets dumped on the wheel/ground. Before, I was usually able to catch most of it (long arms help), but when I missed some, it was always at the start, which is where the water would be.
 
I found a few drops of water in school planes that sit outside when I was training.
I only remember one time finding a drop in my own plane. It's hangered I put new fill cap gaskets on it years ago and they still fit tight.
I sump right after fueling.
 
I’ve found it from time to time over the decades.

On my own hangared planes, I can’t remember when I last saw water and I sump before first flight of the day

I’d look into your fuel source and maybe even purge out your fuel system.

Glass gasolator bowls are nice for this type of thing
 
Before the first leg of every flight and after every refuel.

I never found water in the plane I trained in, but it was well-maintained and hangared unless it was out flying. The very first plane I rented afterwards was pretty much the opposite - maintained to a "safe" level, but not beyond, and tied down outside. I sumped almost a full jar of water out of one of the tanks before fuel came out. I had always wondered during training if I was silly for being so fastidious about sumping, but after that, I decided I didn't mind being silly if it meant avoiding preventable engine troubles or crashes.
 
As mentioned above, I also used to find some in the school’s 150s that sat outdoors when I trained. Never much. My old 172 sat in a hanger, but it leaked a lot. Did keep the sun off the plane. Would find a little now and then. Never found anything in the current plane.
 
Found a cup and a half of brown murky water in a flight school 152 that lived its life outside. Scrubbed the flight.
 
Sump every flight and after every refuel. Have never found water in my hangared personal plane (piper arrow). But have several times in flight school planes (C172) that sit outside. But even then, just a very small amount. Did sump probably a quart of really dirty looking water out of a military helicopter once (OH-58C). Also parked outside.
 
I think this is a great question, that's really more than one question...or that's dependent on what you're flying.

I always sump before flying. If I'm getting fuel, local airport, I'll sump before getting fuel. If I'm getting fuel someplace else, I'll take a break, 10-15 minutes or so, after fueling before sump.

Maybe 3-4 times, total, I've found water in a wing tank in a PA-28. Usually less than an ounce, once more than 3 vials full, in all cases clear water, no dirt. Once was in a plane that had flown that day, apparently just running on the other tank. In all cases I drained the water, started on the other tank but did the taxi and run up on the tank with water. I believe in all cases it was either a gasket problem on the fuel fill, or I suppose possibly that the cap wasn't put on correctly. These are aircraft that were usually stored outside. I've never found water in the gascolator of a PA-28, but I check it each time.

Just me, I'd never trust "water pooling" or seeing droplets from draining on the ground. Concrete in its natural state is porous, and natural asphalt is rough. I don't think either of those surfaces, uncoated, will bead water. Shiny smooth sealed asphalt or clear sealed concrete might, but I don't fly from anywhere that is that fancy..and even if I did, draining fuel onto the ground doesn't seem like a great thing to do.

So anyway, maybe I'm crazy, but in a PA-28, after finding clear water and then getting gas, I'm good with a bit of idle, a 1/2 mile taxi and run-up and then flying. Not suggesting to anyone that's safe or correct, just that I've done it.

The aircraft that would make me nervous would be those with bladder tanks that could have folds in them, combined with water. I don't think I'd love having or flying one of those where it was stored outside. I've seen people do the wing waggle thing before, and that's not a thing that inspires confidence in me, anyway.
 
Only once so far in my Saratoga and that was right after refueling. I Find water constantly in the rentals but they all live outside right next to the ocean so it’s constantly damp at night.
 
I can see humidity condensing in the tanks, but I don't get the concept of water leaking into the fuel system. If water leaks in, fuel would leak out. More likely the water comes from the supply.
 
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