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Jet Ski Oil (Difference in 2 Stroke vs 4 Stroke)

Confusion regarding which Jet Ski Oil to choose can be quite a bummer. However, knowing the engine type of your Jet Ski makes the job easier. Jet Ski Oils should be chosen depending on the type of engine of the Jet Ski.

To make this job easier and to help my audience get a better grasp on this topic, I have discussed what kind of oil goes in a jet ski in specific cases. 

A 4-stroke Jet Ski uses a 10W-40 Marine-grade Certified Oil, whereas a 2-stroke Jet Ski TC-W3 oil. Both Jet Ski types must use NMMA FC-W specifications marine-graded oil. The variation in oils used stems from their difference in lubrication requirements.

Asides from answering some of the most popular queries about the differences in these respective engines, we would also like to provide further insight into the type of oil that is best suited for them.

If you want to learn more about the type of engine to go for then be sure to stay with me till the end of this article.

What Are the Differences Between 2-Stroke and 4-Stroke Engines?

To understand why you should use different oils for 2 stroke and 4 stroke engines, knowing about their function first is a must. So, let’s take a look at how these two engines function. 

Fuel-Consumption Rate

Let’s talk about fuel consumption now. Since 4-stroke engines are newer and have more investment put into them, they are made to be far more efficient.

Given that the gasoline in this sort of engine is burned per four strokes, the four-stroke engine is significantly more efficient. 4-stroke engine Jet skis supply a lot of power while also maintaining a balanced fuel consumption rate.

Even if 2-stroke engines are not on par with 4-stroke in terms of performance, they still fail to make up in terms of fuel consumption.

Not only do they have inefficient engines, but are also prone to gas leaks and smaller tanks. They usually run out of fuel faster and require refueling every 2 hours.


Let’s talk about the basic mechanisms of the functionality of these engines. We are not looking forward to diving too deep into this section, however, it will not hurt more to learn about the functionality of these engines!

The primary distinction between a 2-stroke engine and a 4-stroke engine is the rate at which the combustion cycle occurs.

The number of times the piston goes up and down during a particular cycle in the engine directly determines this.

The piston of a 2-stroke engine goes up and down just once throughout the combustion cycle, whereas the piston of a 4-stroke engine moves up and down twice during each revolution.

One similarity is that both of these engines are internal combustion engines.

In contrast to 2-stroke engines, 4-stroke engines have ports for pulling in fuel and air, they also have intake and exhaust valves. Whereas, 2-stroke engines only have 2 ports for the fuel outlet and inlet.

Their difference in engine mechanisms plays a vital role in asserting the right oil type for each Jet Skis.

Fuel/Oil Mixing

This is only applicable for 2-stroke engines as the pre-mixing of oil and gasoline is required for these engine types. 

A 2-stroke engine differs from a 4-stroke engine in this case given that it lacks an internal oil reservoir.

Instead, the owner of a two-stroke engine must add oil into the gasoline at a specified ratio to guarantee the engine receives appropriate lubrication during the operation whereas 2-stroke engines use the added oil in the combustion process.

You can learn more about the mechanisms that lead to fuel mixing in the 2-stroke engine Jet Skis.

What Jet Ski Oil Should You Use for a 2-Stroke Engine?

Any brand of oil TC-W3 marine vehicle-specific certified oil would do. Mix it in proper ratios with gas if an oil injection pump is not available with the Jet Ski.

Let’s talk about 2-stroke engines in a deeper sense. As mentioned above, 2- stroke Jet Skis need a reservoir of both oil and gas to run.

The oil acts as an essential component in making it run. However, it doesn’t necessarily have to be high-grade expensive oil.

TC-W3-rated oil that is simple to find, reasonably inexpensive, will just about do the job.

If you want a recommendation then I suggest going for Yamaha 2W (Costs around $25/gallon).

Keep care for older 2-stroke engines that require you to maintain a specific gas to oil ratio.

If you have a 2-stroke Jet Ski with an oil injection pump then simply fill it to the max and relax.

Although I do not deem it necessary, you can always go for premium synthetic oils like AMSOIL, MOTUL, and others.

Yes, Ester-based oils provide better combustion and protection, however, the advantages do not make a gigantic change as you may expect.

Thus, stick to the conventional oil with sufficient detergency and lubricity if you have to!

What Jet Ski Oil Should You Use for a 4-Stroke Engine?

4-Stroke Jet Skis usually make do with 10W-40 Marine-grade Certified Oils. Make sure the brand you chose meets the NMMA FC-W oil specifications.

Just choose any brand of 10W-40 NMMA FC-W specifications approved Oil. If you want brand suggestions go for Kawasaki, Yamaha, and Suzuki. Just make sure that they are specified oils for 4-stroke Jet Skis.

It is of utmost importance you only use marine oils as they have components that protect the engine from wet environments.

During seasons, a process called absorption can take place where water may mix with oil and corrode the insides of your oil in the winter.

Hence always be sure to change your oil reserves every 50 hours of usage and use fresh engine oil.

Difference Between The Oil Used for 2-Stroke and 4-Stroke Jet Skis

Since the previous section has provided us with how each engine functions and their difference in mechanisms, we now want to move on to the discussion of the difference in oil used for these two engines.

The primary difference between these two types of oil is their lubrication requirement which stems from their difference in combustion systems.

Oil for 4-stroke engine Jet Skis

In the case of 4-stroke engines, a continuous flow of filtered oil lubricates the engine. Oil is circulated throughout the engine by the oil pump to lubricate, cool, and clear engine components.

The oil eventually drains back into the sump, where the pump circulates the oil throughout the engine in a continuous loop.

The crankshaft of a 4-stroke engine is partially submerged in the oil sump to facilitate splash lubrication. The rotation of the crankshaft causes oil to spill onto other engine components such as the engine.

An oil pump is used in pressurized lubrication to supply a pressured layer of lubricant between moving parts.

Oil for 2-Stroke Engine Jet Skis

The purpose of lubricating oil in a 2-stroke engine is unique as it is burned during combustion in a two-stroke engine.

That’s why in most current two-stroke Jet Skis it is necessary to pre-mix oil and gasoline in a gas can or add oil to a reservoir that steadily depletes.

Furthermore, with a 2-stroke engine, combustion happens on every revolution of the crankshaft, as opposed to every other revolution in a 4-stroke engine.

This creates more heat and puts more strain on the lubrication.

Detergency and lubricity are two important characteristics of an oil that must be considered to safeguard the engine and extend its life.

These qualities are what draws the line between a 4-stroke and a 2-stroke Jet Ski engine.


That pretty much wraps up the basic bits about what kind of oil goes in a jet ski. As you can see depending on the type of your engine the answer can be very different.

Hoping this article has answered all your questions regarding Jet Ski Oils, I wish you all the best ahead! 

Thanks for reading till the end and have a wonderful day.