Inboard vs. Outboard Motor: Which One Should You Choose?

The motor of a boat can greatly impact the type of boating activities that you can enjoy, as well as affect the maintenance costs of owning a boat.

While there are many different maritime engines and power choices available, there are four main types: inboard, outboard, sterndrive (inboard/outboard), and jet drive/propulsion.

If you are thinking of purchasing your first boat or upgrading the one you already have, you will come across many choices regarding the boat's motor, namely choosing between an inboard and an outboard motor. This article will go into detail about these two power choices and their pros and cons.

Inboard vs Outboard: Two Different Types of Engines

An inboard outboard engine is typically a car or truck style engine that mounts inside the boat usually lower in the hull, coupled through the transom or the rear of the boat. This engine follows back to an outdrive unit that hangs down below the bottom of the boat. In an outboard engine, on the other hand, both its madhouse and lower unit are bolted to the rear of the boat. Therefore, the entire engine rests outside the boat. 

Pros and Cons of Inboard Engines

An inboard motor or a sterndrive engine package unit offers boat owners a much smoother and almost car-like driving experience. As these engines are very similar to car engines, with the help of its car-based platform, driving a boat with an inboard motor will resemble driving your car. Moreover, they are also much quieter and more fuel-efficient than outboard motors. 

Inboard engine on a sailing yacht

Besides, they have better build quality, which means that they have a much longer lifespan. Due to their popularity and to the fact that currently there is also more after sales boating equipment and accessories available, you can easily find inboard engine components on the market. Boat aesthetics also benefit from it; boats can have an open swim platform at their rear side, without any disruptive visual engine.

Powerboat equipped with inboard engine showcased at the 2022 Palma International Boat Show

The cons of this type of motor are that it takes up space on the boat, which means you will usually fall short, when trying to make room for your friends. Moreover, maintaining and winterizing the boat is more expensive as almost all faults will require professional assistance. Plus, these engines tend to have more components, making them heavier.

Pros and Cons of Outboard Engines

Outboard motors are more compact than inboard motors, which means that they take much less space on a boat, providing passengers with additional room. Another pro of outboard engines is that they are very light in weight and easier to work on.

Moreover, outboard engines are also great for people that like to handle easy repairs and replacements without any assistance. Hence, outboard engines offer a lower maintenance cost, which is ideal for a boat owner that is tight on their budget or does not have easy access to a marine dealership. 

Mechanic carrying out repairs to inflatable motorboat engine

Another advantage of choosing this type of engine is that it helps you extend the season since the engine is immune to freeze damage. Besides, it also allows you to completely trim up the prop and drive the unit out of the water. Trimming up the prop and drive unit makes the boat very beneficial for shallow water access operations and also if you are fishing in saltwater regions.

Triple outboard engine of a powerboat

Despite its many pros, outboard engines also have a few cons. The first is that they are louder than inboard engines. Therefore, they may not be ideal for people that are looking to boat peacefully and quietly with their friends and family. Secondly, outboard motors are also older with regard to current technological standards, which means that they are much less fuel-efficient than inboard motors. Some even argue that the outboard motors are disruptive to the aesthetic appeal of a boat.

Frequently Asked Questions

Which Type of Motor Is More Fuel-Efficient?

Since inboard motors are based on the engineering framework of cars and have newer components, they are more fuel-efficient than outboard motors. 

How Do You Choose the Right Engine for Your Boat?

Choosing the right engine will depend entirely on the type of boat, your boating needs, and your budget. An outboard engine is commonly seen on pontoon boats, bass boats, aluminum fishing boats, smaller boats, and speed boats. The choice comes down to personal preference. If you know that you are going to extend the season, then it is best to stick to an outboard engine.

What Are the Advantages of an Inboard Motor?

Besides being more fuel-efficient, as already mentioned, they are quieter and easier to drive. While you can find inboard motors commonly on mid-sized and larger cruisers, you are less likely to find them on small to mid-sized boats because they suit larger cruisers that usually host parties and events on the sea.

Why Are Outboards so Popular?

Outboard boats are becoming increasingly popular in the bowrider market. You will also see them getting installed in some small cruisers, as outboard power is more flexible in saltwater environments.

As you can see, both inboard and outboard motors come with pros and cons. If you are concerned about fuel economy, quietness, and efficiency, then we recommend you to pick an inboard motor. On the other hand, if maintenance costs are something that matters to you and you have a small boat that you want to use ruggedly, then it may be better to settle with an outboard motor.