Keep Your Motor Running

Understanding your engine's needs and choosing the correct oil and fuel for your boat are paramount to protecting your engine and getting the most out of your boat.

Use the correct oil and fuel

Your boat’s engine powers your on-water adventures, so keeping it well maintained helps you make the most of your time on the water. Using the right type of fuel and oil is critical for your boat engine’s performance and lifespan.

As the U.S. government considers expanding the sale of gasoline blends with 15 percent ethanol (E15), boaters need to be more vigilant than ever when filling up at the pump. On top

of being prohibited by federal law in boat engines, E15 causes significant damage to your boat, and could result in a breakdown on the water.

While most new engines are four-stroke, a large number of two-stroke engines are still on the water. Being aware of which type of engine you have, and the appropriate oil to use, will go a long way toward keeping your boat on the water.

Protect your engine – know the E15 issue

Choosing the right fuel is critical to the performance and life span of your boat’s engine. Fuel that contains 10 percent or less ethanol is the only type of fuel you should use—anything higher, such as E15 (fuel with fifteen percent ethanol) could damage your engine.

Unfortunately, the Environmental Protection Agency (EPA) is working to allow the sale of E15 from June 1 through September 15 – prime boating season. Consequently, E15 will become more prominent in the U.S. marketplace in the coming years so you need to be aware.

Tests conducted by marine engine manufacturers under the direction of the Department of Energy’s National Renewable Energy Laboratory concluded that E15 fuels damage marine engines and cause them to exceed EPA emission standards. As

a result, E15 is banned from use in marine and other smaller engines – including generators, motorcycles, mowers, and trimmers.

However, most people are unaware of this danger. And lifting the restriction on E15 sales during the summer months will make misfuelling more likely, especially for the 95 percent of boaters who fill up at their local gas stations.

While retailers that choose to sell E15 fuel must post warning labels at the pump, the labels are often not easy to spot or understand. Marinas carry gasoline without ethanol and are probably the safest place to fill up if you don't want to worry about fuel. Remember, if fueling up at your local gas station, only use fuel with less than ten percent ethanol.

Understanding your engine’s oil needs

There are two main categories of marine outboard engines: two-stroke and four-stroke. The lubrication requirements of two-stroke and four-stroke engines are very different because of the way each system works.

In two-stroke engines, the oil is mixed with the fuel and lubricates the engine as it passes through. It burns along with the fuel and exits via the exhaust system. Four-stroke engines are lubricated by oil that is repeatedly pumped from, and returned to, a sump, just as in a car or truck.

Although oil in a four-stroke marine engine performs the same function as it does in an automobile engine, passenger car motor oil should not be used in marine engines. The two primary reasons for this: water and wear.

Oils made for cars are not designed to provide the high level of

corrosion protection marine engines require. Additionally, because four-stroke outboard engines run faster than car engines, spend a long time running at extreme speeds, spend long periods out of use, they have very specific requirements for anti-wear protection that car oils do not provide.

The best way to protect your engine is to use the outboard engine oil recommended by the engine manufacturer or to look for the NMMA TC-W3® or FC-W® logo on the oil can. The marine industry tests and certifies oils to ensure they meet marine engine needs. Use the following list to determine the correct oil for your boat’s engine:

- TC-W3® oils are certified for two-stroke engines.

- FC-W® products are certified for four-stroke marine engines.

- FC-W® Catalyst Compatible covers oils intended for use in four stroke engines that have an exhaust after-treatment catalyst.