Bad Avgas

cowtowner

cowtowner

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Cowtowner
Is there a lab I can send some avgas to get tested?

I could write a whole history of this that has had my plane down for the last two months, with me telling two different mechanics that I think it's bad gas.....to finally getting a mechanic to drain the tanks and put fresh fuel in to find out, ah, problem solved.
 
As an Airport Manager, I would like to know more information. Between the Airport and the supplier, there are several quality control measures that should prevent a discrepancy. I’d be puzzled if you really did receive bad fuel and would be curious how it happened. Have you notified anyone about it?
 
I notified the airport, but you see, the airport is in Mexico. They weren't too concerned as I made it home.
 
cowtowner said:
I notified the airport, but you see, the airport is in Mexico. They weren't too concerned as I made it home.
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Ah, well, who knows what their handling practices are there.
 
cowtowner said:
Is there a lab I can send some avgas to get tested?
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Blackstone does gas testing. But its a bit expensive as it takes a special HAZMAT mail kit to send. I've had better luck contacting a local fuel distributor for testing or a recommendation.
 
cowtowner said:
Is there a lab I can send some avgas to get tested?

I could write a whole history of this that has had my plane down for the last two months, with me telling two different mechanics that I think it's bad gas.....to finally getting a mechanic to drain the tanks and put fresh fuel in to find out, ah, problem solved.
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It sounds like you already know?
I have my doubts that it is “bad”
It cost a fortune to have any kind of fuel tested. If you find a place they won’t want to do it for a individual.
Best way to test it is to put it in your lawnmower. If it doesn’t run right then you will know and all you have to do is dump it out and replace with fresh fuel.
Pretty simple to drain your fuel tanks on your plane without getting your mechanic involved. I use a shaker siphon to drain my tanks. No tools needed or AP mechanic.
How old is the fuel ?
 
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Salty said:
What is the purpose of having it tested? What will be done with the results?
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Exactly...If I had a dollar for every time someone asks if we can test fuel I'd be rich.
I have sent countless customers to 2 different fuel testing places here in town and no one has ever had it done once they find out how expensive it is.
One visual test is to look for bright and clear fuel with no water in it. Placing it in clean white buckets is a good way to check for water. So is water paste for checking inside the fuel tank. I siphoned this fuel out when I replaced a fuel tank in my 172. Dumped it right back in to the new fuel tank with no filtering because I could see that it was clean. Put that baking tray over those buckets for a couple days while the tank was replaced. I drained the tanks outside in front of my hangar. If I put it in fuel jugs then there is another chance of dirt getting into it.
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The reason for testing is to determine if it was bad.

The fuel was put in the plane in Mexico and then flown home to Texas. From takeoff it didn't feel right

it's not about water, the mechanic thinks there is something like mogas mixed in It has a distinct odor.
 
cowtowner said:
The reason for testing is to determine if it was bad.

The fuel was put in the plane in Mexico and then flown home to Texas. From takeoff it didn't feel right

it's not about water, the mechanic thinks there is something like mogas mixed in It has a distinct odor.
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Doesn’t answer the question. What are you going to do if it’s bad? What are you going to do if it’s good?
 
Way back before the Mo- gas STCs some well known company was going to market a Tester to test suitability of mo- gas for aircraft use. I think it tested Reid Vapor Pressure ( RVP).

I have flown with really old Av- gas with no issue.

At one time 2 aircraft about 70 miles apart had problems that turned out to be
bad mo- gas . My bud; “ Crude Dude” tested the fuel and found it high in xylene.
They had split a load of fuel.

Crude Dude had taken down a refinery and about 15 years later they were clearing the land and found a substantial amount of 100 LL. It still tested good.
 
cowtowner said:
The reason for testing is to determine if it was bad.
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You already figured that out ...

cowtowner said:
The fuel was put in the plane in Mexico and then flown home to Texas. From takeoff it didn't feel right it's not about water, the mechanic thinks there is something like mogas mixed in It has a distinct odor.
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I live on the border, years ago in high school we'd fill up across the river in Juarez Mexico, but ONLY used the highest octane available. We'd see them mix "a little water" into their tanks, but not on the high octane grades. Check color, feel and smell for 100LL ... probably wasn't water or you'd have seen it when sumping ...
 
Let's say you figure out the fuel was bad. The FAA helps you make that determination.

Next step: Mandatory engine tear down, fuel system tear down, lots of $$$ down the drain. Why? Because you ran "known bad" fuel in your airplane.

Do you really want to go there?
 
cowtowner said:
it's not about water, the mechanic thinks there is something like mogas mixed in It has a distinct odor.
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What sort of odor? Maybe some Jet-A or other fuel was left over in in the transport truck or somewhere else along the way.

I've never done the test, but conventional wisdom to test for Jet-A in avgas is put some on a piece of paper, and if there is an oily residue after it evaporates, it is Jet-A or diesel.
 
clear_prop said:
Maybe some Jet-A or other fuel was left over in in the transport truck or somewhere else along the way.
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I obviously cannot speak for Mexican practices, but here in the States, the two are never trailered on the same truck. They have dedicated trailers for each product.
 
My hangar mate received a load of MoGas from a local FBO that didn't seem to "run right". I tested a sample by adding a small amount of water (about 5%) to determine if there might be alcohol present. Sure enough, the water volume doubled, meaning fuel tested about 5% alcohol. Going back to the FBO and the delivery system the MoGas fuel was "certified" as E0 from the manufacturer (i. e. non-alcohol) fuel but somewhere along the line had been mixed with E10. It had been put in airplanes for about 6 weeks. Interestingly the credit card company refused the FBO's efforts to track back to anyone else that might have had this E5 mixture.

The small-amount-of-water test is easy using a test tube. Look for any tendency for the apparent water volume to increase when mixed and shaken with a fuel sample.

Obviously it isn't a complete test, but it will quickly detect the presence of non-hydrocarbons.
 
OK, when I did organic chem, they included compounds that were predominately hydrogen and carbon.
 
cowtowner said:
The reason for testing is to determine if it was bad.

The fuel was put in the plane in Mexico and then flown home to Texas. From takeoff it didn't feel right

it's not about water, the mechanic thinks there is something like mogas mixed in It has a distinct odor.
Click to expand...
I’d sue. Does Mexico have lawyers?

I knew a guy who got diesel fuel for his boat out of drum at the dock in the Caribbean. Unfortunately, it had some mogas mixed in. Immediately upon start up, blew a connecting rod out of the side of the block. He had to go get a new engine on his own dime.

I’d be glad I got home in one piece. Drain all the fuel out of the plane and replace with new and move on.
 
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