Should you Be Using Non-Oxygenated Fuel?

Ok, So I recently shot a video about non-oxygenated fuel. When doing my research and putting my thoughts together, I thought it would help to just write a paper at the same time. So below is the full paper for you to read in full or skim. Also, make sure to check out the youtube video! As always, thanks for reading.

Using non-oxygenated fuel in small engines such as an ATV or side by side has been a hot debate for years. I have seen (and been a part of) many arguments as to why you should or should not be wasting your time and money being concerned with non-oxygenated fuel. There are a few reasons that seem to be the theme when this argument arises, the first of which is that if you are not using non-oxygenated fuel you are actually using an ethanol blend, which pulls moisture out of the air, leading to water in your fuel tank. The second is that oxygenated fuel actually oxygenizes the aluminum parts in a fuel system and damages them. The final big theme is that ethanol breaks down and will end up clogging your engine (or at least parts within your fuel system).

               Before digging too deep into these three themes it is important to fully understand what the difference between non-oxygenated gas and “regular” gas is. Regular gas is blended with ethanol (usually as E10) and used as an oxygenate. Non-Oxygenated fuel is basically the exact opposite. It is considered a more “pure form” of gasoline and has 0% (E0) ethanol. In 1990, the clean air act mandated the use of ethanol fuels because they produce less pollution. Additionally, the argument can be made that using ethanol actually assists North America in being less dependent on foreign oil as 10% of gas is being replaced with 10% ethanol.

               With this slightly better understanding of what separates “regular” gas from non-oxygenated gas, it would appear that regular gas would actually be a better option. So why then does it often seem to receive such a bad name? The first is the claim that ethanol (which is an alcohol) actually pulls water out of the air, lending to phase separation, and ultimately leading to water in your fuel tank and lines. This issue can result in frozen lines, corrosion, misfires, and overall poor performance. This myth has been around for years and is rumored to have been started by oil companies because ethanol is classified as a hygroscopic substance. Hygroscopic substances can attract moisture from the environment…which has been switched over the years to mean absorb water.

               The Auto Channel did a great job at breaking this idea down to a basic way of understanding the concept and acknowledging that it has been a very large play on words. According to them, if alcohol (ethanol) is so good at pulling water right out of the air, it should be easy to fill a cup half way up with alcohol and watch it fill up by pulling water out of the air…except that the alcohol will evaporate and your cup will be empty. (, n.d.) They go on to state that cotton is also a hygroscopic substance, so then should it not also absorb water right out of the air? Yes, you can place a cotton ball immediately adjacent to some water and it will soak it up, however it does not simply suck it out of the air. The point being made is that ethanol does not reach up and pull water out of thin air. With that idea out of the way, the argument can then turn to the idea that water can form from condensation entering the tank. This is true however, that has nothing to do with the type of gasoline used. Condensation can form as a simple environmental factor and is not associated with ethanol or any hygroscopic action (a great way to avoid this by the way is to always keep your fuel tank full when sitting for periods of time).

               With this idea of ethanol pulling water out of thin air crushed, there is still this idea that phase separation is a cause of ethanol use from standard gas. Phase separation occurs when an excessive amount of water enters the fuel tank, which can lead to the ethanol and water mixing and sinking to the bottom of the tank. This mixture can cause the engine to malfunction as well as cause corrosion within the fuel system (NREL, 2016). While this is a true statement, the amount of water required to oversaturate E10 gasoline is rather high. To help put it into perspective, it would take over 12oz of water in a 20gal tank to reach the point of saturation and begin depleting the ethanol and causing a reduced octane level (Mercury Marine, 2016). To help clarify the idea that phase separation is somehow caused from ethanol is should be noted that ethanol blends hold more water without phase separation versus non-oxygenated fuels. Meaning that phase separation is more likely to occur with non-oxygenated fuels over ethanol blends.

               While phase separation is a real thing, the amount of water that would have to enter a fuel tank is rather high. Again, ethanol does not suck water out of thin air, meaning that somehow water would have to be introduced to the fuel system. Here is where it actually gets ironic. Unlike non-oxygenated gasoline, ethanol is able to mix with water and can help keep water out of your fuel tank by slowly passing small amounts of it through the fuel system without issue! Therefore, as it turns out, using ethanol can actually assist in doing the exact opposite of the claim. It assists in keeping water from sitting in your fuel tank by slowly mixing with gasoline and pushing it through your engine. According to Mercury Marine, after an initial transition period E10 may actually be superior to E0 as a marine fuel as it tends to keep low levels of water moving through the fuel system, keeping the system dry (2016). The same then could be said for off-road vehicles then as they are also often subject to large amounts of water.

               Since ethanol blends do not actually reach out and pull in water but ironically having the ability to push water through the system helping keep it dry, it would appear that this myth is in fact false. The second argument made, which can go hand in hand with ethanol pulling in water and creating phase separation, is the oxidization process. There is the idea that when phase separation occurs, the water and ethanol mix can cause corrosion with all of the metals in an engines fuel system. Once it is clear that ethanol does not pull in water, and phase separation is not a direct result of simply using regular gas this argument pretty much ceases to exist. Like the water argument, it can also be argued that since ethanol helps push water through the fuel system burning it up, regular gas can actually help prevent corrosion of metals due to oxidation.

The third argument is that ethanol blends break down and cause sludge, ultimately clogging your fuel system. This argument does have some valid points, but they are often taken out of context. Firs, all gasoline breaks down over time, not just ethanol-based gasoline. On a side note, once this is suspected the fuel should be replaced. There is no magic mixture you can buy which fixes gas that has already been separated. Remove the fuel from the system and replace with fresh gasoline.

               The argument about ethanol clogging engines is said to have started when individuals running E0 make the switch to E10 had begin having issues. This is most likely not cause by the E10 gasoline but is in fact due to the transition. Since E0 gasoline does not mix with water, there is almost undoubtably water in the bottom of the fuel tank. When E10 is introduced, it will mix with the water in the bottom of the fuel tank, allowing that layer of water and sludge from the bottom of the tank to reach the fuel pickup point and enter the system. Now all of that sludge and water end up running through the fuel system, causing clogs and poor performance. Therefore, this issue is not actually caused by the ethanol blend itself, but the transition process. The fix for this is to actually drain and dry the fuel tank and lines prior to transitioning to E10. Additionally, a good fuel cleaner should be considered as a way to help clean deposits from within the fuel tank and engine.

               After further review, it would appear that the arguments made against ethanol blends are not true. Ironically, some of the arguments as to why ethanol blends are bad can actually said to be more of a reason as to why you should consider using E10 over non-oxygenated fuel (after a proper transition process). On a final note, the resources used to write this paper are below. Primarily because credit should always be given where due. Secondly however, it shows that sources gathered were not simply from the EPA making an argument for pro ethanol blends. For example, it is a safe bet to assume that Mercury Motors is going to tell customers to do what is best for their products. If E10 was causing poor performance or wrecking their engines, they would probably not hesitate to inform customers to simply stick to non-oxygenated fuels.


Cooper, G. (2016, September). Water uptake of ethanol-gasoline blends in humid environments. Retrieved from

Kluge, B. (Director). (2011). The myths of ethanol and fuel care [Video file]. Retrieved from

Rauch, M. J. (n.d.). Ethanol does not suck water out of the air. Retrieved May 5, 2018, from