Fuel color

Tom-D

Tom-D

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Tom-D
I got this sample from a wing low point today.

thoughts ?
 

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Its got bugs in it or it's really old gas (not 100LL).
 
Old Mogas in my bike looked like that after she sat for a while. Or is that the 130octane green?
 
Any one thinking mis fueling? Diesel is yellow, 100LL is blue, combined it gets green.

The Plugs look like they have been burning charcoal.
 
The old 100 Grade (which largely started disappearing about the time I started flying in the early eighties) was green.

The dies are supposed to cancel each other out when mixed together. Frankly I'd suspect mold (which implies water).

I can see JET A being put in, but Diesel? We don't even have Diesel around our airport (they run the tugs etc... on JET A as well).
 
Tom-D said:
Any one thinking mis fueling? Diesel is yellow, 100LL is blue, combined it gets green.

The Plugs look like they have been burning charcoal.
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Easy enough to check, mix a little diesel & 100LL and see what ya get. I'm thinking that it appears to be a bit dark to be mixed fuel but it could just be my screen.

Fuel & oil change just to get it out of the aircraft?
 
Where have you been fueling up at?
Did you get a teaspoon of that to compare?
Looks like corrosion products to me, from either water or mogas...
Drain, flush, and refill...
 
flyingron said:
The dies are supposed to cancel each other out when mixed together.
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:yeahthat:

I burn a mix of MoGas and 100LL. The blue is gone with very small amount of MoGas. A gallon or less in a 27.5 gallon tank is all it takes for the sumped fuel to be clear.

It takes three or four fill ups w/ straight 100LL for the color to return.
 
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A little trick that most pilots know is to get a sheet of paper towel, then pour a small amount of the suspect fuel on it. Let it dry (about 10 mins) and then look at the spot. If there is a ring around the spot, the fuel is contaminated. If you see nothing then it is probably OK. 100LL drys without leaving a mark, a ring around the spot could mean jet fuel, or diesel fuel is in it.

BTW the last time i was in Hawaii, I seam to remember the fuel to be red because the only fuel they can get is 120-130 octane. I had to pour an additive into the fuel to decrease the relative octane level.
 
Someone urinate in the tank?
 
Garthur said:
BTW the last time i was in Hawaii, I seam to remember the fuel to be red because the only fuel they can get is 120-130 octane. I had to pour an additive into the fuel to decrease the relative octane level.
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Why? Too little octane--bad--detonation. Too much octane--waste of money but not harmful. And isn't red 80 octane?
 
contaminated 100LL turns clear -

Could be some corrosion X somewhere -
 
If it tastes the same as last time, just go fly.:goofy:
 
Looks like fuel that grabbed the glue from sealant tape as it leaked out perhaps?

(When Cessna bladders go there's often goo everywhere along with all the blue streaks... Just a guess... since you like to teach...)
 
Witmo said:
Why? Too little octane--bad--detonation. Too much octane--waste of money but not harmful. And isn't red 80 octane?
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Red indeed was 80 (what we knew as 80/87). 100 was green, and we knew that as 100/130. 115/145 was purple; it was for the old high-compression piston engines found in fighters and bombers, IIRC. 91/96 was brown. If they ever make 82UL it will be purple, too.

Dan
 
Garthur said:
BTW the last time i was in Hawaii, I seam to remember the fuel to be red because the only fuel they can get is 120-130 octane. I had to pour an additive into the fuel to decrease the relative octane level.
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That makes no sense whatsoever. I suspect that you have somewhat misremembered.

Red was 80 octane.

There would be no reason in the world to add an additive to reduce octane in a gasoline engine.

A quick check in Skyvector suggests that 100 (green) is the fuel that is available in Hawaii

But, back to the original question, what color do you get when you mix 100LL and a ton of Marvel Mystery Oil?
 
It's a positive GA Pregnancy Test ... young lady pilot's got a leaded bun in the oven
 
denverpilot said:
Looks like fuel that grabbed the glue from sealant tape as it leaked out perhaps?

(When Cessna bladders go there's often goo everywhere along with all the blue streaks... Just a guess... since you like to teach...)
Click to expand...

That sample came directly from the bottom drain of an aluminum tank.

I really don't know what this.

but

What would you guys do with the fuel in the tanks, fly it out?
 
Tom-D said:
That sample came directly from the bottom drain of an aluminum tank.

I really don't know what this.

but

What would you guys do with the fuel in the tanks, fly it out?
Click to expand...

What is the condition of the fuel caps?
 
Tom-D said:
That sample came directly from the bottom drain of an aluminum tank.

I really don't know what this.

but

What would you guys do with the fuel in the tanks, fly it out?
Click to expand...

What does it smell like?
 
Tom-D said:
That sample came directly from the bottom drain of an aluminum tank.

I really don't know what this.

but

What would you guys do with the fuel in the tanks, fly it out?
Click to expand...

I assume you kept sumping until you got a good sample. If the contamination was not water, I would want to know the source of the contamination before flying.
 
vintage cessna said:
I assume you kept sumping until you got a good sample. If the contamination was not water, I would want to know the source of the contamination before flying.
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It ain't going any where until I know what it is.

What does a mix of 3 auto to 2 100ll look like?
 
Dan Thomas said:
Red indeed was 80 (what we knew as 80/87). 100 was green, and we knew that as 100/130. 115/145 was purple; it was for the old high-compression piston engines found in fighters and bombers, IIRC. 91/96 was brown. If they ever make 82UL it will be purple, too.

Dan
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Good memory, Dan. I burned a lot of purple AvGas (115/145) in ~1200 hours of flying the old Spad ...i.e., Douglas Skyraider, aka AD-6/7, aka A-1H/J ...R-3350 up front.
 
Tom-D said:
It ain't going any where until I know what it is.
Click to expand...

The sample smells like avgas? Does it evaporate quickly if you dump it on something? Does it leave an oily residue?

The picture looks exactly like the color of the gas/oil mix for my two stroke snowblower.
 
Capt. Geoffrey Thorpe said:
The sample smells like avgas? Does it evaporate quickly if you dump it on something? Does it leave an oily residue?

The picture looks exactly like the color of the gas/oil mix for my two stroke snowblower.
Click to expand...

I still haven't talked to the owner, but I think it's a auto mix. an old auto mix.
 
Has someone been transferring fuel using contaminated portable jugs? Looks the color of 2-stroke fuel/oil.
 
The fuel in the picture has the appearance of 100/130, if it's indeed avgas, but also has a swirled black charcoal appearance like it's contaminated with something. I'd have guessed colored water from the appearance, though the original poster states that it's avgas.

I haven't seen 100/130 in quite a while. (and 80/87, and 100/115 in even longer).

I'd certainly be for boroscoping the engine, flushing the system, checking seals, bladders, etc, and examining what fuel filtration may be available in the aircraft.

Anytime fuel of an unknown quality or source has been run through, it's best to check.
 
DouglasBader said:
The fuel in the picture has the appearance of 100/130, if it's indeed avgas, but also has a swirled black charcoal appearance like it's contaminated with something. I'd have guessed colored water from the appearance, though the original poster states that it's avgas.

I haven't seen 100/130 in quite a while. (and 80/87, and 100/115 in even longer).

I'd certainly be for boroscoping the engine, flushing the system, checking seals, bladders, etc, and examining what fuel filtration may be available in the aircraft.

Anytime fuel of an unknown quality or source has been run through, it's best to check.
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did you read that this sample came fro the bottom drain of an aluminum tank?

The owner came by the hangar today, we talked about this and he had no clue as to what I was referring to, So I pulled another sample and showed it to him.

He said I'll be right back, and in about 30 minutes he shows, and says drain all the fuel and get fresh, he thinks his kid put 5 gallons of #2 diesel fuel in each tank, because the tractor's 2, 5 gallon cans of diesel fuel are empty. and so is the tractor.

If it doesn't look right, it probably ain't.
 
Tom-D said:
He said I'll be right back, and in about 30 minutes he shows, and says drain all the fuel and get fresh, he thinks his kid put 5 gallons of #2 diesel fuel in each tank, because the tractor's 2, 5 gallon cans of diesel fuel are empty. and so is the tractor.

If it doesn't look right, it probably ain't.
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Yikes.

Both for the guy, and because he has a really dumb kid. That will make both their lives harder. :) :) :)
 
denverpilot said:
Yikes.

Both for the guy, and because he has a really dumb kid. That will make both their lives harder. :) :) :)
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He'll learn by his mistakes, we all do. By now he's probably burping shoe leather.

If no one ever taught you any thing, would you be smart or ?
 
did you read that this sample came fro the bottom drain of an aluminum tank?
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Yes, I did, which doesn't change my reply. There's more to the fuel system than that one tank.
 
DouglasBader said:
Yes, I did, which doesn't change my reply. There's more to the fuel system than that one tank.
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There certainly wouldn't be any "Bladders" would there?

yep there is more than that one tank, a shut off for each tank, and glass gascolator, and the carb which has a brass needle valve and seat.
 
Good professional call on taking the time and effort to follow through on this; the owner is really lucky that you found this and followed up, rather than someone saying "Huh, wrong color,but no water" and continuing on....
 
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