Find exactly what you're looking for...

Disadvantages of Ethanol Fuel & Additives

Disadvantages of Ethanol Fuel & Additives

Boating 101: Disadvantages of Ethanol Fuel & Other Additives

If you have invested in purchasing a boat, chances are you are going to want to take extra care of it, so no issues arise. While routine maintenance is vital to keep your boat in tip-top shape, so is the fuel that you add for your engines. In the marine industry, it is highly encouraged to add fuel that does not contain ethanol for marine engines; but as we all know, finding gas in today’s world without ethanol is becoming quite rare. Let’s take a look at some of the disadvantages of ethanol fuel and the use of additives.

What is Ethanol Fuel?

ethanol fuel

Ethanol is highly refined alcohol, approximately 200 proof, which comes from natural products like corn or sugar cane and wheat. Over time, alcohol has become a fuel additive to bring upfront costs down. Three common types of fuel found on the market currently are E0, E10, and E15. E0 meaning 0% ethanol, E10 is 10% ethanol and 90% gasoline, and E15 meaning 15% ethanol. 

Why is Ethanol Harmful For Boat Engine/s?

Although ethanol-blended fuel is widely used, studies are now sharing the dangers of ethanol to fuel tank systems and engines, especially in the marine industry. Issues that can arise from using ethanol fuel in your boat include phase separation and deterioration of fuel system components.

Phase Separation

Phase separation is the separation of water and ethanol from fuel within a tank. When water is present in a tank, it bonds to the ethanol molecules in the fuel. Once the mixture of water, ethanol, and fuel reach a certain point, the ethanol and water will drop to the bottom of the tank and separate from the fuel. Once this occurs, you are in danger of severely damaging your motor. 


In addition, boats with a fiberglass fuel tank are in great danger of deterioration. Ethanol will break down certain resins that hold the glass fibers together, allowing debris to potentially reach your motor. Fiberglass is just one of the materials that ethanol will deteriorate. Rubber, plastic, and even some types of metal can deteriorate over time. All of which are part of your fuel tank system. Many boaters will mix additives to try and counteract the effects of ethanol, but that is an intricate and uncertain way of dealing with the problem.

Disadvantages of Fuel Additives

Like ethanol-blended fuel, additives have been around for quite some time. These additives serve as a way to boost octane and preserve stagnant gas for extended periods. Additives are also being designed specifically for ethanol treatment. Although this may solve the problem of phase separation, additives are pricey and can be harmful to engines.  

The problem lies in the many different types of fuels available throughout the country. Major oil companies all have their own blend packages that they add to fuel, each going through a distinctive refining process and having different Reid Vapor Pressures.  It’s very doubtful that additive manufactures have tested their products with every type of fuel available. Would you trust your multi-thousand/million dollar investment on chemicals that may be incompatible with the fuel you put into your boat? Not to mention, no chemical agent or fuel additive can be added to E10 gasoline, in a reasonable quantity, that can completely prevent phase separation or recombine a phase-separated layer.

Keep Engines & Fuel Tank Systems Safe | Benefits of Non-Ethanol Fuel

AMI fuel docks

Since ethanol-blended gasoline has become so widely used, most boat and motor manufacturers claim to have adjusted their manufacturing processes to allow for the use of E10 gas. However, long-term effects are still unknown, and this doesn’t rule out the above information. Play it safe when it comes to your investment. The benefits of using non-ethanol fuel (or REC 90) far outweigh the savings of using a blended source. Here are some tips and benefits of using non-ethanol fuel. 

  • One gallon of gas can provide more than a third more energy than the same amount of ethanol, providing better overall mileage.
  • Using non-ethanol gas allows us to be less dependent on crop production for fuel.
  • Compared to traditional gas blends, E0 has a longer shelf life. This is vital if you don’t have a regular boating routine. 
  • Locate a marine refueling station. Marine stations are the best option to ensure you’re getting the proper gasoline for your boat and reducing the risk of damages caused by ethanol-blended fuel. 
  • Check the pump to be sure that it is dispensing non-ethanol fuel. Some gas pumps at local gas stations may offer E10 and E15 or have blender pumps that dispense mid-level ethanol fuels. 


Related Articles:

Boating 101: Protecting Marine Wildlife

Cited: GoBoating



Compare (0/3)

Back to Top