Fuel Tanks - Permanent & Topside, Fuel Lines, Connectors, Filters & Gauges
Impact of Ethanol-Blended Gas on Boat Engines
Article courtesy of Tom Bingham, Gold Eagle, Co.
Warmer weather has finally arrived across most of the country, and it's time to clean up your boat and get it ready for the open waters. But, before you fill up your boat's fuel tank, there are some things you should know about ethanol-blended gasoline and its impact on your boat.
Research has found that as much as 75 percent of boats serviced at the beginning of boating season require carburetor cleaning due to build-up from oxygenated fuels. Oxygenated fuel is gasoline that contains oxygen, which is predominately caused by ethanol that is mixed into today's gasoline at the pump.
How Can Ethanol Impact Your Boat Engine?
If a boat is left in storage for more than three weeks with ethanol-blended gasoline such as E10 or E15 in the tank, you could experience any or all of the following:
Phase Separation - Ethanol is alcohol-based, and alcohol absorbs moisture from the atmosphere as it sits, causing engine corrosion. As time goes by, the mixture of gas and water separate, and the water sinks to the bottom of the fuel tank, creating two separate solutions. When this happens, it's called phase separation, which is bad news for a boat engine. When a boat is first started and gets moving, the bow rises, and the water-soaked ethanol solution is pulled into the engine, which can lead to misfire and costly repair fees.
Deterioration Issues - Ethanol is a known solvent and can affect the interior of rubber hoses and cause deterioration of the materials. Tubes that run to the fuel tank overtime can become brittle, break off or flake. Broken pieces could travel through the fuel lines and eventually clog the fuel system. For boats with fiberglass fuel tanks, ethanol can also corrode and even dissolve the fiberglass resin that holds the material together, causing major issues.
What Can You Do?
Most of the country now has gasoline-blended with ethanol (E10) at their local gas stations, and finding non-oxygenated fuel is very difficult and expensive, costing as high as $5 to $8 per quart. But, before you empty your wallet and pound the pavement looking for ethanol-free fuel, there are some things you can do to prevent the side effects of gasoline that contains ethanol.
Do Your Homework - Take the time to look over all systems of your boat, especially your fuel hoses and primer bulb. Take them in your hand and feel for stiffness or signs of the hoses becoming brittle. Prime the bulb several times prior to starting your engine and visually check as well as "feel" for leaks. Sometimes leaks occur in out of sight locations. Also, smell for fumes or possible leaks. A small amount of gas fumes are common, but if you smell a very strong odor of fuel, there's probably a leak somewhere.
Fill Your Tank - If you are using ethanol-blended fuels, make sure to run your boat on fresh fuel and keep the tank 95 percent full (to allow for expansion). A tank that is nearly full reduces the flow of air in and out of the vent, which reduces condensation on the tank walls. Condensation that does form will be absorbed by the gasoline. If possible, park your boat in a shaded area during storage or at least cover the fuel tank if it's exposed. This will aid in minimizing condensation in the tank and discourage corrosion.
Add an Ethanol Treatment - In response to ethanol-blended gasoline, there are new solutions on the market to protect your engine from the damaging effects above. Ethanol treatments like Marine Formula STA-BIL include corrosion inhibitors, cleaners and fuel stabilizer to help protect your engine. At every fill-up, add a bottle of ethanol-treatment to your tank to prevent the gasoline and ethanol from separating, attracting moisture and causing corrosion. By adding a treatment at EVERY fill-up, you not only protect your system from everyday problems with ethanol, but also the long-term problems should you not be able to use your boat as often as you'd like.
Drive Your Boat Regularly - Use your boat frequently during the season to ensure your gasoline doesn't get stale in your fuel tank, which helps protect it from phase separation. If you're unable to physically drive your boat, for any extended time more than 30 days, at least make sure and start it up using a set of "muffs" available from your marine dealer and a common garden hose. Your engine should be run a minimum of 15 minutes per month to insure all fluids are warmed and circulated. This will discourage corrosion inside the engine and keep your fuel system fresh with the stabilized fuel. Tom is director of marketing at Gold Eagle Co., industry pioneer and maker of America's No. 1 selling fuel stabilizer, STA-BIL®, and 303® Products. Tom has six years of experience in the performance chemical industry and seven years in the outdoor power equipment industry and is a certified small engine mechanic.