Are 2 Stroke Outboard Motors Good & Reliable | Answered

Until late 1990, 2 stroke outboards were pretty standard outboards that were found on most water bodies. With the come of 4 stroke competition, many manufacturers stopped building 2 strokes. The 2 stroke outboards were very good and reliable.

There has been an ongoing debate between 2 stroke outboard and 4 strokes outboard for a long time. With the popularization of 4 strokes, many people have started to doubt 2 strokes and see them as inferior to their counterparts. Many countries have banned the usage of 2 stroke outboards as they were seen as a hazard to the environment. It is clear that that debate does not have a clear answer, as both sides have merits and demerits. Let us examine how good and reliable are 2 strokes are and why they were eventually phased out.

A little History of 2 Stroke Outboards

The use of 2 stroke outboards are registered in 1913 in Germany. These were primitive 2 stroke outboards that consumed huge amounts of oil and there was a lot of lag in the engine performance.

Reverse Flow Scavenging is a technology that was used in 2 stroke outboards to improve their performance. This technology ensured that the piston traveled in the reverse direction of the exhaust gases. This helped to evacuate the combustion chamber effectively and improved the engine performance. As time passed these outboards were perfected for harsh marine conditions and performed very well.

How Good and Reliable Are 2 Stroke Outboards?

2 stroke outboards are very good and reliable. These outboards provided a lot of power and torque as they burned a lot of fuel on every cycle. This increased the efficiency of the overall performance on average. These were also cheaper compared to their counterparts as they were easier to produce, assemble and maintain. 2 stroke engines had a very long shelf life.

2 stroke outboards have fewer moving parts when compared to 4 strokes outboards. This means that they are more reliable and durable. They do not require a lot of maintenance and are very easy to repair. These engines also have a longer lifespan than 4 strokes outboards.

2 stroke outboards are small in size and easy to handle. They are also lightweight, making them easy to handle and carry around. These outboards were mostly used in small boats. Their lightweight made it easier to row the boat with a 2 stroke engine. However, they produce a lot of noise when compared to 4 strokes.

2 stroke outboards provide great acceleration, as they burn a lot of fuel on every cycle. This increases the overall efficiency of the performance. 2 stroke outboards are also a lot cheaper to produce and maintain.

How Do 2 Stroke Outboards Work?

2 Stroke outboards work on the principle of internal combustion.

The 2 stroke outboard usually consists of an in-line two-cylinder engine with opposite pistons to produce crankshaft torque in one direction.

There are 2 spark plugs in the cylinder head of the motor for each cylinder. This ensures that there is always a fresh mixture in the combustion chamber.

The 2 stroke outboard has a crankcase, where the lower half serves as a reservoir for lubricating oil, and the upper half forms part of the engine’s compression chamber. The lower end of the crankcase is sealed by a crankshaft and main bearing cap which also supports the propeller.

The inlet system consists of an inlet manifold with a throttle control chamber, fuel supply system, air filter, and one or more carburetors. The exhaust system has a water-jacketed cylinder head for each cylinder, which is fitted with a reed valve or rotary vane-type piston valve for exhaust gases.

2 stroke outboard engines are always started by electric start, this ensures that there is proper lubrication in the engine components while cranking the motor.

The 2 stroke technology also saw its use in personal watercraft, snowmobiles, lawnmowers, and other small engines.

How Long 2 Stroke Outboards Last?

2 stroke outboards were a popular choice for boat motors because they were affordable and easy to maintain. However, there are some factors to consider when deciding whether or not to buy a 2 stroke outboard. One of the most important is how long it will last.

2 stroke outboards usually last for between 1,200 and 1,800 hours of use. This means that you should expect to replace the motor after between 5 and 10 years of use, depending on how often you use it. It’s important to keep in mind that this is just an estimate, and your particular motor may last longer or shorter than this.

If you’re looking for a durable and reliable boat motor, then a 2 stroke outboard may be a good choice for you. However, if you want a motor that will last longer than this, then you may be better off with a 4 stroke outboard or one of the other types of outboards.

Why 2 Stroke Outboards Are Phased Out?

2 stroke outboards have been phased out because they are no longer as efficient as 4 stroke outboards. 2 stroke engines produce more pollution and noise than 4 stroke engines, which is why they are not as popular anymore. Additionally, 4 stroke engines are more reliable and last longer than 2 stroke engines. For these reasons, most boat manufacturers now only offer 4 stroke outboards.

2 stroke outboards produce more pollution than 4 stroke outboards because they burn a lot of fuel on every cycle. This increases the overall emissions from the motor. Additionally, 2 stroke engines are noisier than 4 stroke engines, which can be harmful to the environment. For these reasons, many boat manufacturers are now only offering 4 stroke outboards.

Some Common Problems with 2 Stroke Outboards?

1. 2 stroke outboards are often known for their high power to weight ratio, which makes them perfect for smaller boats. However, they also have a few common problems:

2. They can be difficult to start in cold weather. It is recommended that the engine temperature be at least 60 degrees before attempting to start a two-stroke outboard.

3. They often have a high oil consumption rate. This means you will need to check/add oil more frequently than with a four-stroke outboard, which typically consumes less oil over time.

4. They tend to be noisier due to the increased vibration associated with two-stroke engines.

5. Because of their high power output, they do not last as long as a comparable four-stroke engine.

6. The lubricating oil also helps to cool the engine as it circulates. It is important to use the right type of oil in a two-stroke outboard, as using the wrong kind can lead to damage and costly repairs.

7. They require more maintenance than 4 stroke outboards. This is because they require maintenance at regular intervals to avoid damage. It’s important to follow these maintenance schedules in order to get the most use out of your motor, and failure to do so can void your warranty.

Are 2 Stroke Outboards Banned?

Some countries and states have banned 2 stroke outboards because of their high emissions and noise levels. Additionally, 4 stroke outboards are now more popular than 2 stroke outboards because they are more reliable and last longer. Strict environmental laws and regulations have caused many boat manufacturers to stop offering 2 stroke outboards.

2 stroke outboards are not banned in all countries, but they may be significantly more expensive than 4 stroke outboards due to import taxes and environmental restrictions. It’s also very unlikely that you will find a new 2 stroke outboard for sale at your local marina or boat dealer.

However, there are still 2 stroke outboards available for sale online and in some marinas and boating supply stores. For example, the Yamaha 2-stroke is one of the most popular 2 stroke outboards on the market. It’s a great motor with an affordable price, but you will need to buy it new and it is not available for sale in all states.

Maintaining Your 2 Stroke Outboard

1. One of the main problems with 2 stroke outboards is that they consume oil at a high rate. It is important to check the oil level regularly and add oil as necessary. Failing to do so can lead to damage to the engine.

2. Check the spark plug

3. Add fuel stabilizer to the fuel tank

4. Inspect the propeller and replace if necessary

5. Keep the engine coolant level topped up

6. Tighten all screws and bolts on a regular basis

7. Use only high-quality 2 strokes outboard oil

8. Follow the manufacturer’s maintenance schedule

9. Have your 2 stroke outboard serviced at least once a year

10. Replace the fuel lines annually

11. Replace the impeller on some models every few years

12. Service and clean all fuel system components every few years

13. Inspect hoses for cracks, splits, tears, or wear after 100 hours of use


When it comes to boat motors, the best option is often a 4 stroke outboard. However, 2 Stroke Outboards have their own advantages and disadvantages that should be considered before making your purchase decision. If you are considering purchasing a two-stroke engine for your boat, make sure you know all of its benefits and drawbacks so that you can weigh them against what’s important to you as an individual boater.