Earlier, all the outboard motors were designed to use 2-stroke engines. With the rise in technology, and environmental concerns playing a part, the outboard motors are now using the 4-stroke engines for the low end machines. There are positives and negatives to each of these engine types.

2-Stroke Outboard Motors:

2-stroke engines are lighter and faster, allowing for more top end speed and acceleration. They are also more affordable and have a higher resale value. Because 2-stroke engines have been around for almost 80 years; necessary parts are more readily available, making repair easier. The design on these engines is less complex than that of a 4 stroke engine, which allows for fewer problems to arise.

For many years, 2-stroke engines suffered a reputation as fuel-slurping, dirty-exhaust outboards. That’s changed. Most of the bigger, conventional 2-strokes have been retired, replaced by state-of-the-art, direct-injected and fuel-injected 2-stroke outboards, available in a bewildering array of horsepower ratings. The new machines are wonderful for the way they conserve fuel and accelerate a boat like crazy.

Boaters who would be most likely to choose a 2-stroke motor are interested in speed, performance, and acceleration. This may be the engine of choice if you own a smaller boat that may not be able to hold the weight of a 4-stroke outboard.

A 2-stroke motor is also suitable if you are more familiar with engine repairs, or even want an engine that is easy to repair and can be brought anywhere to be fixed. If you are not required to operate in a body of water that is for four stroke engines only, you may want to purchase a 2-stroke. If you would like the most power for weight of the engine, or interested in more speed, acceleration, and performance; a 2-stroke motor is for you.

There are also some cons to buying a 2-Stroke outboard motor. These engines are not as environmentally friendly, and produce more smoke and pollution. In the non oil injection models, it is necessary to mix gas with oil. These outboards are noisier, have a rougher idle, and are sometimes difficult to start. There are also some problems with spark plugs fouling.

Manufacturers of 2-stroke outboards include Evinrude, Yamaha, Nissan and Mercury.

4-Stroke Outboard Motors:

4-stroke engines are quieter, smoother and more economical. Heavier with slower acceleration, they are normally chosen for lakes and rivers. With less pollution and smoke they are also kinder to the environment. If you’re after a quieter, smoother ride, then the 4-stroke outboard is the better choice.

4-stroke outboards are more complicated with more parts so they often require repairs more often. When repairs are needed they tend to be more expensive and spare parts can be harder to source.

4-stroke outboards are generally heavier than 2-stroke outboards, so if you own a smaller boat it may not be able to hold the weight of a 4-stroke engine.

Because 4-stroke outboard motors are newer, they are continually being improved to make purchase and repair easier. And depending on whose numbers you believe, from 70 percent to 80 percent of all outboards sold are 4-strokes.

Some 4-stroke outboard motor manufacturers include Johnson, Honda, Mercury, Nissan, Suzuki, Tohatsu and Yamaha.