100LL avgas was introduced in the 70s. At that time, a fuel system lubricant called Fuel Lube was used to lubricate rotating components subject to fuel immersion (mixture controls, fuel valves, etc). In the 90s, Fuel Lube seemed to no longer be effective and would harden and ball up with the 100LL blend. At the same time, 100LL seemed to take on a different characteristic both in smell and evaporation rates. Small leaks no longer left stains on the hangar floor, for example.
Then EZ Turn was introduced as a “high octane fuel lubricant.” It worked better than what had been used previously. The old Fuel Lube became obsolete.
There is no doubt the industry can move past these hurdles, but testing and fact finding should really be in a controlled environment, not on the ramp.
I wonder if exposure to sun (ultraviolet) light could skew the results? GAMIs test was in a lab, not in the sun.
John Beatty:
But I’d want specifics of your person’s tests.
Such as brands and types of paint tested.
Paint varies.
Paint ages.
(And note the article says Braly is testing on panels from a Beech Bonanza. He used to own one, presumably used its engines to test G100UL.)
Gatorade:
The ‘control’ needed is type of paint, age of it, and environment aircraft stored and flown in. (Such as hanger, sunshine, …)
(BTW, have you tested Gatorade on aircraft paint? 
Surely someone has noticed the effect of 100LL on paint when it drips from a leaking fuel drain onto a wheel pant. The solution for paint damage from either 100LL or G100UL spills is to avoid spills and replace leaky drains.
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I’d like to see independent testing done. An impartial entity doing thorough testing would put a lot of minds at ease one way or another. Ideally it wouldn’t be the manufacturer of the product nor someone who simply does not want the product. Just facts please.
This is why GAMI needs to get ASTM certification. Testing will be done the same, per a standard, in the same conditions, and same circumstances. This is the only way testing will be consistent, verifiable, and comparative.
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We’ve been over this argument before - ASTM does not provide for what you think it provides for.
Do we know for whom Michael Luvara works? Where is he based? Does he have a “dog in the fight” that is hidden from obvious view? Did he create these videos as a marketing effort to drum up more business (knowing that most of his potential clients oppose change of any kind).
Even though I’m an advocate for the small guy, Michael’s sudden appearance on the scene does raise questions of its own. We know Braly’s position and biases and can make a determination as to our trust in his work, but we have no such history with Mr. Luvara.
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Yes, but G100UL is a new thing, so people are focused on every little thing they notice with it, even if it’s something they’ve seen before with 100LL. It’s not a blue stain, it’s a yellowish stain, so that’s new…
Isn’t the RAMP the best real world scenario there is?
And great, if there’s an issue, call it out. But GAMI’s FAQ says: After extensive testing, no compatibility issues have been identified in any aircraft, engines, storage tanks or transportation systems. G100UL avgas is a “drop-in” fuel, fully fungible with 100LL and other aviation gasolines, and ready to be used within the industry’s existing infrastructure."
Did they not test with something so well known as the current iteration of Fuel Lube?
Wouldn’t you want to know if there was an issue with today’s “Fuel Lube” aka “EZ-Turn” like there was when 100LL was introduced?
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I had never heard of either until it was mentioned here. No mechanic or pilot I’ve ever talked to has mentioned either product, and I don’t recall seeing it mentioned in any of the usual aviation publications, so I’m not sure how “well known” it is.
My point being, there’s no way any replacement for 100LL can be tested with every possible combination of engine/airframe modifications or additives, in the same way that airframe/engine STC modifications can’t possibly be tested against every possible combination available.
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I spent 34 years in the metal cleaning / coatings removal business. Some paints are less affected by solvents than others: for instance Alumigrip has better solvent resistance than Imron. Imron can be wiped off with MEK and a rag. Alumigrip is resistant to most solvents and is unaffected by MEK.
But Brian Hall, GAMI has detailed elements of the ASTM ‘standard’ that are not appropriate, and pointed to omissions.
Swift may also have pointed to problems applying the present ASTM ‘standard’ to its products.
Why aren’t objectors pushing ASTM committee members to do their job?
(Honestly of course, I’ve seen defects in ARINC standards for avionics, some of them deliberately inserted to block new technology.)
Another oddity of forum display is that some of my posts have a red 1 and red editing symbol where the name of poster I’m replying to would normally be, upper RH corner.
Doesn’t correlate to newness of post, nor missing name as still occurs with some posts.
If you’ve flown or owned a Piper PA-28 airplane with the sidewall fuel valve installed, Fuel Lube or EZ Turn has been used to lubricate the brass cone in the brass valve body in order to ensure the detents are identified and operation is smooth. In 50 years of maintenance, I’m not sure I mentioned what was used to any client. All he wanted was a valve that worked and was easy to turn.
I would venture to guess that most all mechanics are familiar EZ Turn (aka ‘fuel lube’). I have a tube in my hangar. Can be used to lube fuel valves, or, for example, I have used it to coat gaskets that are exposed to fuel. I coated the gasket that seals the float valve to the bottom of my fuel tanks. No leaks.
All I can say is that I am not ready to experiment with my airplane to see if G100UL will damage it in any way - either paint (which is costly to repair) or gaskets, o-rings, hoses or other components that are essential to the safety of flight. I would be delighted to use any fuel in my aircraft that does not have lead, but not at the expense of failure of components. I suspect that my airplane will fly just fine on 93 octane UL mogas for which there is an STC, but I am an architect, not an engineer, so I need to rely on experts, not folks with a vested interest. I am not saying that Mr. Luvara is right or wrong, but he does bring up valid points and concern.
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correction to my post: not float ‘valves’, just floats for the transducers.
Best I can find is he works for a company (electric vtol wisk?) that has no skin in the game on keeping 100LL around: Flight Plan Podcast
Based on test pilot and mechanic background seems to be cautious or genuinely curious after availability of the new fuel?
Good points - the real issue includes questioning who is an expert in this context, it seems.
When I was getting my A&P license ~2000 Cessna had a AD warning that fuel control valves needed to be disassembled and checked for “Fuel Lube” - it needed to be removed. Their where accidents attributed to it.
I considered the same … The old Imron was a two step paint that would stand up to just about anything but DuPont removed it from the market and the common paint after that was JetGlo from Sherwin Williams, a water based paint.
I suspect the aggressive solvents in 100UL (Toluene) are melting the water based paint.
Imron is back on the market but I don’t know the resistance difference between Imron of today and Imron thirty years ago.
This whole topic is nonsensical. It’s a complete waist of time. Russ throws these 100UL blog candy topics out there when he needs a little blog action.
The photograph is showing an improper fueling technique that could lead to a fire from static electricity.
A more responsible photo would show the nozzle in contact with the tank.
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Exactly. Static electricity can build in the fuel flowing out of the nozzle and a spark can jump to the filler tube resulting in a bad day for the operator. Keeping the nozzle touching the spout and having a ground cable attached completes a ground circuit and prevents any static buid up.