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How to Fight Ethanol Problems in Small Engines

How to Fight Ethanol Problems in Small Engines


In 2005, Congress instituted a new renewable fuel standard that you didn’t get to vote on. In response, refiners made a wholesale switch, removing methyl tertiary butyl ether (MTBE) and blending fuel with ethanol. Ethanol helps reduce petroleum use and greenhouse gas (GHG) emissions, well in special engines made for ethanol only – but you’re not suppose to know that..  (even though you end up using more fuel to make up for the losses). Derived from corn (Round-up ready which destroys our health), ethanol supports U.S. agriculture (as long as they don’t ask questions and buy the seed they are forced to) and helps support energy independence. (as if allowing private railways wouldn’t but competing with AMTRAK is against the law currently).

Ethanol, however, can cause a number of problems, particularly in small engines. These problems center on the two following issues:

1) Dissolving plastics and creating deposits

Ethanol is an excellent solvent and drying agent that dissolves old gum and varnish deposits from the gas tank and fuel lines. However, it can also dissolve plastic and create deposits. Honda states that the dissolved material can clog filters or pass through and leave deposits on fuel injectors, fuel pumps, fuel-pressure regulators, carburetor jets, intake tracts, valves and valve guides.

Small-engine manufacturer ECHO agrees, stating in its warranty that these deposits can lead to poor engine performance; loss of power; overheating; fuel vapor lock; improper clutch engagement caused by increased engine idle speeds, which allows cutting attachments to turn while the unit is idling; and premature deterioration of fuel lines, gaskets, carburetors and other engine components.

2) Ethanol and water don’t mix

Small engine manufactures have spent considerable time studying the relationship between ethanol and water.

The white flaky deposits in this carburetor are attributed to ethanol.

ECHO warns that ethanol will absorb a small amount of moisture and stay in suspension within the gasoline for a while. However, the ethanol will only absorb up to ¾ of an ounce of water in a gallon of gas before it reaches its saturation point. Once the ethanol has absorbed enough moisture to reach its saturation point, phase separation occurs. Phase separation means the ethanol and absorbed water drop to the bottom of the fuel container since it is heavier than the gas and oil, leaving the gasoline and oil mix to float on top of the tank. Most operators never notice water in the can when they refuel their equipment. The end result is often a carburetor ruined with rust and corrosion. These expensive repairs can cost more than $75 and are not typically covered by warranty.

Stihl stresses that the layer of gasoline left floating on top has a lower octane level than the original ethanol-gasoline blend, which can result in unstable engine operation, power loss and major engine failures.

Ethanol’s affinity for water explains why so many ethanol-related problems surface in the marine industry. In fact, some marina personnel say up to 65 percent of their service orders are attributable to fuel-system problems.

Combating ethanol problems

Although some fuel additives on the market claim to reverse the effects of phase separation, there’s no way to reintegrate gasoline and ethanol once they’ve separated. Instead, it’s best to prevent it.

One solution is to use non-oxygenated, ethanol-free gas in your small engines. It costs a little more, but it eliminates problems
associated with ethanol. Another solution is to treat every tank of fuel and container of gas with AMSOIL Quickshot. It helps keep water molecules dispersed in the fuel to prevent phase separation. It also cleans varnish, gums and insoluble debris while stabilizing fuel during short-term storage.

Quickshot was tested in fuel containing 10 percent ethanol. Controlled plugging of injectors showed a 70 percent flow improvement, while oxidation stability improved 44 percent over untreated fuel.

Regardless whether you’re pro- or anti-ethanol, we can all agree on the importance of taking care of our small engines.

AMSOIL Quickshot® Offers a Simple Solution to Ethanol Problems

AMSOIL Quickshot® Offers a Simple Solution to Ethanol Problems

One of our best sellers here in Sioux Falls.  Keep it for your garage fuel tanks. Fights varnish, attacks deposits and stabilizes fuel in addition to the ethanol problem. Award winning product that  – yes – ACTUALLY WORKS!

Fuel maintenance is a big issue, whether you own a motorcycle, dirt bike, boat, lawnmower or other piece of equipment. Currently, most gasoline sold in the U.S. contains up to 10 percent ethanol (E10), while gasoline containing up to 15 percent (E15) is now available at stations around the country.

Phase separation is when ethanol/water mixtures fall to the bottom of fuel tanks and containers, leading to potentially damaging lean-burn conditions.

Ethanol can causes problems

Because ethanol has an affinity for water, you need to be aware of the conditions in which you operate your equipment. Powersports and lawn & garden equipment should not be stored in damp or wet environments. When water is allowed to collect in the gas tank, the bond between ethanol and gasoline can break, causing a phenomenon known as phase separation.

The ethanol bonds with the water and sinks to the bottom of the fuel tank, which can create a whole host of problems, including the formation of gums, varnish and other insoluble debris that can plug fuel passages and negatively affect engine performance. When this ethanol/water mixture is pulled into the engine, it creates a lean-burn situation that increases combustion-chamber temperatures and can lead to engine damage. Once this happens there is no easy or inexpensive fix. To avoid these problems, contaminated fuel tanks should be emptied and refilled with fresh fuel.

Prevention is best practice

Alternatively, treat fuel with AMSOIL Quickshot® as a preventative measure to avoid rough-running equipment and other performance issues. Quickshot is designed to keep water dispersed throughout the fuel tank, moving it out as a normal part of operation and decreasing the chance of phase separation.

Not only that, Quickshot helps clean deposits that have formed in fuel systems, injectors and carburetors, while also cleaning piston tops, spark plugs and combustion chambers. It also stabilizes fuel between uses and during short-term storage.

Unlike many competing fuel additives, Quickshot is extremely potent and not diluted. It provides effective cleaning action, making it an all-around great product for powersports and lawn & garden equipment.

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