Sumping Technique

[Seth]

Due to the information on other threads about water in the tanks, I did not want to hijack another thread, so I created this one:

I usually sump first before doing anything else (sump then check oil) during preflight because that way the wing is not stirred around and water won't move away from the sump.  Once oil and fuel suping (and visuall checking fuel levels) are completed, I then finish the preflight, or pull the plane out of the T-hanger and then finish the preflight. 

After fueling up, either a truck filling up or at a self serve pump, I do not sump, as the fuel has stirred everything around, and there is no real point to, or at least that is what instructors have told me time and time again (though that may not be correct - hence one of the questions below).  If the truck fills up my plane at my hanger, I always sump before the truck arrives when the fuel and hopefully any potential water, has settled to the sump.  If I go flying right then, I'll not sump.  if I put the aircraft back in the hanger, I'll sump during the next pre-flight.

Every time I start the engine, I sump both the right and left feeds from the center pull up ring inside the cabin on the floor, regardless if I just landed a short while ago and it's a hot start or not.

I have never found water in the Mooney tanks, but if I did, I would sump an extra two or three fuel testers worth and then gently rock the wing and check again.  i have found dirt/debris in the past while sumping, but that was rarely.

Questions for Mooney pilots:

1.  When do you sump during your pre-flight?

2.  Do you sump after new fuel has been added? 

3.  Does rocking the wing actually do anything, or will water collect regardless at the sump location?

4.  Has anyone found water in their tanks after leaving their aircraft in a hanger (maybe hard IFR flight or bad fuel - or bad hanger roof!!)?

5.  Does anyone reuse fuel that they sump?  Do you use a filteter device and place it back in the wing or put it into a generator or other motor device for actual fuel use?

Not trying to stir the pot, just seeing what others do to enhance my own standard operating procedures.

Take care,

-Seth

 

[Shadrach]

I sump first flight of the day.

I rock the wings a bit before doing so, as water will travel to the sump if it is dispalced from any other place in the wing.

I also sump after adding fuel.

As to pumping fuel "stiring up the water...I beleive that it will temporarily stir the water about, but I do not beleive that will tate a long period of time to redeposit in the sump after fueling. I have never gotten any significant water out of a Mooney tank; the few time that I have small amounts of water has been shortly after being fueled by a truck. YYMV.

Inspect and replace those o-rings folks...it's cheap insurance. I always order a back up set when I replace them (every2 to 3 years), they are inexpensive. A properly maintained fuel cap should prevent water issues.

So many folks neglect the inner "shaft o-ring". It does not matter how well the outer ring seals if the inner is leaking water around the shaft... 

[rbridges]

call me cheap, but I reuse my sumped fuel.  My is strained, and (knock on wood) I have never seen any water in my fuel.

[N601RX]

The Moonies with bladders have a pretty large sump.  The pickup is about an inch off the bottom and 3 or 4 inches away from the side. It would take at least a couple of quarts or even a gallon to get up to the pickup, so if you sump regularly, there shouldn't be any problems.   I assume the factory pickup is similar?

[Ron McBride]

I sump at the first flight of the day, and 10 minutes after fuel is put in. I put in new O-rings every year. I have found water in 1 tank only after the plane was sitting in a hanger a couple of times. We readjusted the cap a little tighter and this problem stopped.

Our fuel caps are used on many types of planes. Maintain them and you should be OK.  I have found lots of water in Cessna and Piper tanks also. I suspect maintenance is a lot of the problem.

I try not to leave my plane outside. In October, the plane was outside for a large rain storm, I did not have any water in the tanks.

If you have your tanks resealed, there are drain holes in the ribs that must be left open so that the water and fuel can crain thru. If these are sealed, water could collect behind these and then when you are flying the water could move to your sumps.

Ron

[MooneyMitch]

Another technique I believe someone mentioned in another thread, after rain or washing the airplane and prior to opening the fuel cap, remove any standing water that may remain in the top of the cap. 

My method for water removal is an aborbant cloth.  This soaks up the water quite nicely.

[scottfromiowa]

I replace all four O-rings every annual.  I always sump and measure fuel quantity in each tank before flight.  I have found fuel in my tank only when line person installed cap cocked.  It is common that they do and they can be really tough to remove if this is done.  If plane is tied down for a week (while vacationing) it is common that water is in the top of the cap (remove carefully), but if on properly I have not sumped water.  I look, smell and sometimes sump twice if I think whole sample might be water...I do NOT replace sumped fuel in tank.

[201er]

I too sump the tanks before the rest of preflight. I have gotten water on several occassions so I am very thorough about always checking. Mainly it was the result of driving rain and a bad ring but there are other ways to end up with water. Smelling the fuel is really important cause one night I took a sample and it appeared homogenous (no bubbles) and it was hard to discern color in low light. But the smell just wasn't strong enough. So I sumped another tank and sure enough that sample floated upon the first and it turned out the entire cupfull was water at first. I ended up sumping about 6 cups of water out of that tank until I got to fuel. And I kept going just to be sure. If I so much as see a drop of water in the fuel, I dump it. But when it is clear I pour back in through gatz jar filter.

I always sump when taking on new fuel. You never know when their fuel tank could have leaked in water. Seth, no offense, but I think your nuts not to sump and inspect the fuel you're putting in! For all you know it could be all water or a few cups worth (which would sink quickly enough to find). You're right that a single drop of water may get stirred up and go unnoticed but what if you're taking on a lot of water? I've read about a guy who landed at an airport (I used to fly out of), got gas, didn't sump, took off, crashed within a mile of the runway and died cause of water in tanks.

I think pouring back good looking and filtered fuel back into the tanks is far safer than skipping sumping all together when refueling. Proper disposal of fuel is usually difficult or impossible. Pouring it back in is not only economical, but it's also a legal way of taking care of sampled fuel.

[aviatoreb]

Quote: Seth

Due to the information on other threads about water in the tanks, I did not want to hijack another thread, so I created this one:

I usually sump first before doing anything else (sump then check oil) during preflight because that way the wing is not stirred around and water won't move away from the sump.  Once oil and fuel suping (and visuall checking fuel levels) are completed, I then finish the preflight, or pull the plane out of the T-hanger and then finish the preflight. 

After fueling up, either a truck filling up or at a self serve pump, I do not sump, as the fuel has stirred everything around, and there is no real point to, or at least that is what instructors have told me time and time again (though that may not be correct - hence one of the questions below).  If the truck fills up my plane at my hanger, I always sump before the truck arrives when the fuel and hopefully any potential water, has settled to the sump.  If I go flying right then, I'll not sump.  if I put the aircraft back in the hanger, I'll sump during the next pre-flight.

Every time I start the engine, I sump both the right and left feeds from the center pull up ring inside the cabin on the floor, regardless if I just landed a short while ago and it's a hot start or not.

I have never found water in the Mooney tanks, but if I did, I would sump an extra two or three fuel testers worth and then gently rock the wing and check again.  i have found dirt/debris in the past while sumping, but that was rarely.

Questions for Mooney pilots:

1.  When do you sump during your pre-flight?

2.  Do you sump after new fuel has been added? 

3.  Does rocking the wing actually do anything, or will water collect regardless at the sump location?

4.  Has anyone found water in their tanks after leaving their aircraft in a hanger (maybe hard IFR flight or bad fuel - or bad hanger roof!!)?

5.  Does anyone reuse fuel that they sump?  Do you use a filteter device and place it back in the wing or put it into a generator or other motor device for actual fuel use?

Not trying to stir the pot, just seeing what others do to enhance my own standard operating procedures.

Take care,

-Seth

 

[MARZ]

I sump all three - first thing on preflight is the gasolator I'm in there lowering the flaps anyway - by the time I'm done with the rest its all evaporated.   The wing sumps don't give me enough to pour back in.

[bd32322]

Quote: rbridges

call me cheap, but I reuse my sumped fuel.  My is strained, and (knock on wood) I have never seen any water in my fuel.

[201er]

I do wing sumps first. Outboard then inboard sumps (monroy tanks). I do the gascalator last. I figure I should sump top down on the system so I could catch any water upstream and possibly sump more downstream if necessary. Especially since I usually don't get to see what comes out the gascalator.

[KSMooniac]

I usually sump... but not always if my plane has been tucked away in her hangar and there hasn't been any precip.  I use the wonderful GATS jar, and pour my sumped fuel back in the tank through the strainer.  I've gotten water in my tanks after sitting outside in a big rain storm and with older fuel cap gaskets.  (It also got in the static system too).  If I'm doing a quick-turn fuel stop I don't sump as it does take quite a while for any water to settle-out in the fuel, and in my limited experience, I've never had water delivered with fuel.  (I worked line service in college, and we had to sump the fuel trucks and fuel farm tanks every day to "open" the airport, and I never found any water there either, even in a very wet climate)

[M016576]

I've had water in my tanks after a storm, and I've also had metal shavings in my tank from a self serve pump that was eating itself and kindly depositing it's metal into my fuel tanks.  I sump after every refuel for that reason... Never know how some of thos older pumps are maintained...

The fuel system is built very well.  You'd have to have a gallon plus of water in a tank to hit the pickup.  If you want to know how long it takes that water to settle out in your fuel, get an empty soda bottle, fill it half way with fuel, then put some water in and watch.  It sinks very quickly.  After moving your plane, it shouldn't take more than a minute or two to be all settled out again.

The prospect of sucking fuel or metal into your fuel line is terrifying, but the sump system in our wing is pretty amazing... Gotta love mooney engineering!

[clh]

I sump before the first flight and after adding fuel. I know it may not be perfect, but I have detected contaminated fuel before. In that instance, they had just changed filters on the fuel tank.  There was not much, but definately enough to ruin my day.  

 

 

[garytex]

I concur with 201er about sumping every time.  When water comes with fuel, it can sometimes come in large amounts.  I caught about 5 gallons of water after a refuel once.  That cured me.

Gary

[Seth]

Thanks everyone - I have changed my SOP and now sump at every refuel as well, not just after the aircraft has been sitting to allow water to collect.

Take care,

-Seth

[jetdriven]

Just ordered a set of o-rings from O&N for my Shaw Aero 457-1150 caps.      140$

 

A new fuel cap?   2 grand!   WTF WTF WTF

[201er]

Here's an NTSB report of a Mooney taking off/crashing from my airport with "large quantities of water." There are so many other mechanical issues that are outside of our control so we must especially take care of the ones directly preventable by our own carefulness.

http://dms.ntsb.gov/aviation/AccidentReports/1bvf1h55fhluwdvj223aazev1/X02032012120000.pdf

[Guest]

This past summer my hangar neighbor left our airport and 15min later landed at another airport, got his cub topped off then immediately took off. Soon after takeoff  he lost power and put the cub down in a lake, the good thing is no one was hurt and it was shallow water. Water was found in the tanks and was traced back to the last refueling point. Not waiting the proper time and not sumping the tanks after re-fueling (to me ) is  a game of russian roulette .

 

[Seth]

As noted, I'm now sumping after refuel, as well as prior to any engine start.  When in the hanger or out on a ramp, I sump first to ensure that any water/debis that may come out is at the sump point.  

After refill, how long a wait is enough?  30 seconds (I'm kidding) a few minutes, 5 minutes, 10 minutes, 30 minutes? 

Thoughts?  And besides your thoughts, what is your actual practice.  As in - "you should wait 10 minutes, but I sump right after I get my reciept/retract the hose/truck drives away."

So - thoughts and then what you actually do.  They can of course differ.

-Seth

[Hank]

Fill tanks.

Pay for same [often inside FBO].

Visit head.

Return to plane, sump.

Actual time varies, depending on walking speed and distance. I see very few fuel trucks . . . often SS pumps.

 

[201er]

Have you ever shaken your fuel tester with fuel + water in it and watched how quickly the water settles to the bottom? While it may take 5-30 minutes for all water to settle to the sump, I think by the time you close your cap, put back the hose, and get your receipt, first signs of water would be sumpable (especially on the tank you filled first). If you so much as get a drop of water, it may pay to wait for it all to settle. But if no sign of water after sumping a whole cup, I think it's safe. I wonder if anyone's opinion differs? Has anyone ever sumped no water on the first try and then found water in the same tank some time later?

[MARZ]

Quote: Hank

Actual time varies, depending on walking speed and distance. I see very few fuel trucks . . . often SS pumps.

 

[DaV8or]

I sump before every flight. If I refuel and I'm going to fly right afterwards, I shake the wings good and then sump. If I'm not going to fly after fueling, I figure the taxi to the hangar or tie down will do the shaking and the sumping before the next flight will catch any water. In 13 years of flying, I have only found water once in a Cessna on a tie down and then it was probably just a few ounces, however I still sump every time. Also Mooney's have a different cap than other planes and deserve extra attention.