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My opinion of the FortNine Youtube Fuel Stabilizer Test

My thoughts on the FortNine Youtube Fuel Stabilizer Test

YouTube contributor FortNine has published a video entitled Can fuel stabilizer kill your motorcycle? During the video FortNine conducts some tests on Sta-Bil, Seafoam, StarTron, STP, K100 and ipone fuel stabilizers. The video concludes that some fuel stabilizers do nothing while others cause harm. However, after viewing the video several times, it’s my opinion that many of the “factual” statements made during the video are either outright false or misleading, and the tests conducted do not in any way represent real world situations.

Let’s start with the first statement regarding left-over gasoline residue

At 2:00, FortNite, in referring to what is in gasoline, states: “There’s a lotta shit, all of which evaporates at different rates. The thinner compounds tend to go first, leaving the heavier additives to gunk up your fuel system.” The video then shows a white powdery layer left on the table after the fuel evaporates.

This statement represents a complete misunderstanding of how gasoline degrades and causes fuel system problems. Gasoline is indeed made up of many different components with many lighter and more volatile compounds. These are the compounds that aide in vaporization and ignition. When you leave gasoline out in the open to evaporate, the lighter and more volatile compounds will evaporate first, so the statement is true as far as it goes. However, as the remaining components are exposed to air, they oxidize and break down, forming gum and varnish. It’s the gum and varnish that clog small fuel passages and injectors and coats your fuel system with a sticky brown varnish, not the fuel’s additives as stated.

At 2:30 the video states: “That’s why Fuel stabilizers are anti-evaporative.” Really? Who said they’re anti-evaporative? FortNine then conducts an evaporation test to prove that all the collected fuel stabilizers actually evaporate more than plain E10 gasoline, leaving you to think that all the samples failed the evaporation test. But the test itself is worthless since fuel stabilizers never claim to be anti-evaporative.

They can’t claim to be anti-evaporative because they’re made from either light petroleum distillates that float on top of the gasoline, or alcohols and gylcols that emulsify or encapsulate water in the fuel. So of course petroleum distillates and alcohols evaporate first when exposed to air. Duh!

Is fuel stabilizer hydrophobic? Hardly

At 3:44 the video states: “And that is why fuel stabilizers are hydrophobic, to prevent gas under the influence of ethyl alcohol from picking up the H2O.” First, fuel stabilizers are not hydrophobic. And what good would that do if they did repel water? That still wouldn’t solve the problem of water in the tank.

So calling fuel stabilizers hydrophobic shows a real misunderstanding on how fuel stabilizers work. There are three types of fuel stabilizers and none of them work by hydrophobic techniques. See this post to more about how fuel stabilizers work.

Rick’s take on FortNine’s humidity test

The video exposes a control sample and treated samples to humidity for 30 mins. The results? The control E10 sample took on 42ml of water. iPone and STP took on 42ml of water, Seafoam 40ml, Sta-Bil 37ml, StarTron 44ml and K100 44ml. The video states that perhaps StarTron and K100 are the two prime suspects in killing fuel systems. But again, this shows a misunderstanding of how StarTron and K100 work.

Since StarTron and K100 fuel stabilizers contain alcohol, it’s no surprise that they took on more water. Alcohol is hygroscopic, so of course they’ll absorb water. That’s a no-brainer. It’s what they do with the water that’s important. StarTron is an emulsifying fuel stabilizer and K100 is an encapsulating type of fuel stabilizer. Let me explain why that’s important.

Since all the samples took on water, the question isn’t really how much each took on, but instead, what the fuel stabilizers DO with the water they took on.

StarTron emulsifies it, breaking the water into micro droplets and suspending it in the fuel. K100 encapsulates the micro water droplets with flammable alcohol to help it burn. The other fuel stabilizers try to prevent moisture from contacting the fuel by floating a layer of petroleum distillates on top of the fuel. The “floating seal” stabilizers do work in some fashion. But they can’t stop water from condensing on the sides of the tank. And once that water drips down into the fuel, it will bond with the ethanol until reaching saturation point, and then it will fall to the bottom of the tank. If the tank is filled with non-ethanol fuel, the condensation will immediately fall to the bottom of the tank.

Rick disagrees with FortNine’s final conclusion

FortNine’s conclusion comes at 7:37: “I take two things from this investigation; first the accomplice to every storage crime is ethanol. So if you can fill your tank with ethanol free gas this fall, do that and don’t worry about the rest.”

Second, if you can’t get ethanol free gas, know that fuel stabilizers don’t generally help

Let’s dissect the first statement that concludes ethanol is the killer. It’s not. Water is the killer. All gas tanks have water because all air contains moisture. As the air in a gas tank is temperature cycled from warm to cold, whatever moisture is in the air in the tank will condense on the sides of the tank and fall to the bottom. And that includes non-ethanol gas.

Ethanol with water doesn’t cause any more damage than non-ethanol gas with the same amount of water.

Now let’s look at the second statement; that fuel stabilizers don’t help.

The next biggest issue with gasoline storage is oxidation and gum and varnish formation. Both ethanol gas and non-ethanol gas will oxidize in the presence of air and both will form gum and varnish. All the fuel stabilizers in this video contain components to dissolve gum and vanish. The video doesn’t even discuss how the samples deal with gum and varnish. Yet it concludes that fuel stabilizers “don’t generally help.” How can they make this statement when they haven’t even addressed the gum and varnish issue?

Filling your tank with non-ethanol fuel with no added stabilizer will result in oxidation that will form gum and varnish deposits. How is that better than non-ethanol fuel that has ingredients to retard oxidation and solvents to dissolve gum and varnish deposits?

Rick’s personal opinion of this video

I believe the tests done in this video don’t prove that fuel stabilizers are worthless. The video doesn’t discuss how fuel stabilizers work or the differences in the operation of the different types of stabilizers. So it’s my opinion that the video doesn’t actually prove anything about fuel stabilizers.

©, 2022 Rick Muscoplat




Posted on by Rick Muscoplat


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