DiscoverBoating

Boating Lifestyle

Boating Lifestyle

There is so much to love, and learn, about boating. That's why we created this library of articles, videos and blog posts to help you throughout your adventures.

Choosing the Right Fuel and Oil for your Marine Engine

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

 
There are two main categories of marine outboard engines: two-stroke and four-stroke. Most new engines shipped today are four-stroke, however, there are still a large number of two-stroke engines on the water. 
 
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 repeatedly is pumped from and returned to a sump, just as in a car or truck
 

Newer boat engines are also engineered to be consumer and environmentally friendly —with reduced emissions and extended lifespans. However, these advanced technologies place severe demand on engine lubricants and make it critical to choose the correct lubricant for your engine. 

Use the right lubricant —Marine and auto oil are not interchangeable.  

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.  

Consider that corrosion caused by water is a primary concern for marine engines. Oils made for cars are not designed to provide the high level of corrosion protection marine engines require. 
 
Car oils also fall short in the protection department. Because four-stroke outboard engines run faster than car engines, spend long periods running at extremes of speed and can 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 National Marine Manufacturers Association (NMMA) logo on the oil. NMMA 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 4-stroke engines that have an exhaust after-treatment catalyst 

Use the right fuel—Understand the Ethanol Issue

Using the right fuel is also critical to the performance and life span of your outboard engine. In Canada as of December 2010, Canada’s Renewable Fuels Regulations require an average renewable fuel content of 5% in gasoline.  Gasoline with 10% ethanol is known as E10, and with 15% ethanol known as E15. E15 is only appropriate for use in flex fuel automobiles or a very small percentage of the newest automobiles.  E15 or anything above it is not recommended for marine engines and can cause serious damage to your marine engine.

 
The key for boaters is to pay attention to the labels and not use E15 to fill up at the pump. Marinas, of course can carry gasoline without ethanol, and are probably the safest place to fill up if you do not want to worry about the gas you are using in your boat.