Checking for Fuel Contamination

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MoonlightVFR
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Checking for Fuel Contamination

Post by MoonlightVFR »

Drain those fuel sumps. How much fuel should I sample?

I drain both wings and the gascolator ? But how much to drain?

Tanks have been nearly empty for a long time. Aircraft in enclosed hanger. Expect some condensation of water droplets?

Sometimes it runs down my arm into my shirt sleeve.


Years ago I read that Airforce One is sump checked after each landing. They supposedly drain one quart into a glass mason jar. Wonder how many drains in main tanks?

Regards
gradyb, '54 B N2890C
bagarre
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Re: Checking for Fuel Contamination

Post by bagarre »

http://www.aircraftspruce.com/catalog/a ... -03386.php

I fill that up for each drain point (tanks and gascolator). If I see ANY water or dirt,I fill it again and again until I get a clean sample.

I only sump if the plane has a chance to settle for 10 or 15 minutes. It doesn't do much good to sump right after topping off.
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Bruce Fenstermacher
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Re: Checking for Fuel Contamination

Post by Bruce Fenstermacher »

I'm more frugal. I drain about a 1/2 a shot glass. Enough to see the water, if any, and fuel. If it's all water, and it rarely is, I drain until I get fuel. If there is crud in the first 1/2 shot I might drain another half shot to see if there is more crud. If there is more crud I might drain until it's gone.

It makes no sense to ever drain fuel right after refueling. I do not know the settling rate but it may take a while for the water to settle out.
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bagarre
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Re: Checking for Fuel Contamination

Post by bagarre »

I pour my sump gas into my lawn mower at the tie down so it doesnt really go to waste.
It's cheap mower and is left out in the weather all year long. Never had a problem with bad gas and starts on the first pull after 3 years of doing nothing it but putting gas in it.
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jrenwick
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Re: Checking for Fuel Contamination

Post by jrenwick »

Exactly what Bruce said. I some states (New Hampshire, for instance) it's a no-no to dump your fuel sample on the pavement, so use one of these:

http://www.aircraftspruce.com/catalog/a ... ueljar.php

This sampler has an integral fine particle strainer, so you can examine the fuel and put it back in the tank, leaving any particles or water drops behind in the jar. Or pour it into the fuel tank of your power-tow, lawnmower, snowblower, whatever.
John Renwick
Minneapolis, MN
Former owner, '55 C-170B, N4401B
'42 J-3 Cub, N62088
'50 Swift GC-1B, N2431B, Oshkosh 2009 Outstanding Swift Award, 2016 Best Continuously Maintained Swift
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Hawkeyenfo
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Re: Checking for Fuel Contamination

Post by Hawkeyenfo »

Gotta love the Republic!!
Fly Navy !!!!

1941 Boeing PT-13D Stearman
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1960 Piper Aztec (PA23-250)
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MoonlightVFR
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Re: Checking for Fuel Contamination

Post by MoonlightVFR »

O.K. I appreciate the comments

Was expecting perhaps a technique to shake off the condensed water droplets adhering to inside of wing tank.

Now we are at a shift to felony of splashing the drain sample onto the tarmack and Birdnest preflight.

I still want to elicit comments on the orig subject " Checking for Fuel Contamination"

However I have a bird nest story of my own.

Decades ago I fondly rememeber the facial expression of my 4 year old daughter as I lifted her up to view inside the open cowl of N2890C. It was a jaw dropping , wide eyed exhalation of a four year old , first time view inside a Bird Nest.
Two (2) beautiful Blue eggs in the Nest. A treasured flying experience.

Regards
gradyb, '54 B N2890C
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sfarringer
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Re: Checking for Fuel Contamination

Post by sfarringer »

I normally take a couple ounce sample from each tank, and from the gascolator.

The only time I have found water was at Oshkosh one year, when I found about a quart of water in each tank. I have never bought fuel at Oshkosh since.
Ragwing S/N 18073
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Ryan Smith
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Re: Checking for Fuel Contamination

Post by Ryan Smith »

sfarringer wrote:I normally take a couple ounce sample from each tank, and from the gascolator.

The only time I have found water was at Oshkosh one year, when I found about a quart of water in each tank. I have never bought fuel at Oshkosh since.
At the fuel prices they were likely charging, you should have insisted on a refund! 8O
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cessna170bdriver
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Re: Checking for Fuel Contamination

Post by cessna170bdriver »

Aryana wrote:I've actually never seen a drop of water come out of the sump of my 170, even when it's left out in the rain with the moats around the filler caps overflowing. I keep the tanks full and when I borescoped them a couple years ago they looked brand new inside. The tanks have never seen MoGas/cargas since we've had it the past 20 years.
I saw a LOT of water in the tanks of the airplane that yours followed down the assembly line, Arash. I flew George Mock's N3543C home from the Shelbyville, IN 170 Convention for him. It had rained quite a bit during the week, and it took about a half hour of rocking the wings and draining the sumps 2oz at a time before I convinced myself that the water was gone.
Miles

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170C
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Re: Checking for Fuel Contamination

Post by 170C »

I like those ASA testing cups because they hold a fair volume and on those rare occasions I do find a few drops of water I rarely find any more on a second test. Also, when preflighting in my hangar, I pour the tested fuel into my tug so its not going to waste.

I am afraid if I found a protected bird nest in my cowling I would be the only one who would know what happened to it :wink:
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ghostflyer
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Re: Checking for Fuel Contamination

Post by ghostflyer »

We have a bright red 1 gallon can in the hangar that every one dumps their drains into . The fuel is then used for cleaning paint brushes , parts and the petrol powered compressor ( stand by compressor in the power fails ) . The compressor has been consuming AVGAS for over 10 years and still going strong . It lives on the back of the truck and goes to remote locations as the need be .
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GAHorn
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Re: Checking for Fuel Contamination

Post by GAHorn »

jrenwick wrote:Exactly what Bruce said. I some states (New Hampshire, for instance) it's a no-no to dump your fuel sample on the pavement, so use one of these:

http://www.aircraftspruce.com/catalog/a ... ueljar.php

This sampler has an integral fine particle strainer, so you can examine the fuel and put it back in the tank, leaving any particles or water drops behind in the jar. Or pour it into the fuel tank of your power-tow, lawnmower, snowblower, whatever.

The GATS jar is the BEST solution for expensive AvGas!
If you have a 16 oz jar (they come in 12 and 16 oz sizes) it only takes EIGHT full, generous, LIFE-SAVING samples....and instead of throwing it on the ramp.... you just got a FREE GALLON OF GAS by pouring it back. :wink:

(In fact, even if the gas is contaminated, it separates the water and junk out... and you can still use it. The stuff often goes into my tractor, lawn mower, trimmer, cultivator, generator, etc.)
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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