Home Diagnosis and TroubleshootingProcesses, Mechanics, and Repairs Outboard Vs Inboard – Which Boat Engine Is The Best?

Outboard Vs Inboard – Which Boat Engine Is The Best?

by Jordan Harris
Outboard VS Inboard

Are you a boat fanatic and you want to learn more about outboard vs inboard types of engines before you make a decision? If that is the case, you are at the right place because we are going to cover a lot when it comes to these two types of boat engines and more.

Getting a proper power source for your boat is key if you want to get the most out of it and for the best budget. Different philosophies in boat engines require different maintenance and also different costs to run. That’s why making the right decision is key if you want to get a proper engine for your boat.

Or even if you want to get a new or used boat. Knowing the ups and downs of each of these engine types is going to save you a ton of money in the long run. And considering the times that we live in. It’s best for you to learn all of these things in order to make the best decision and not lose a ton of money in the long run. Because you don’t want to end up in a money pit full of problems. You want the best for your budget. But don’t worry cause we are going to help you out.

In this article, we are going to learn what is inboard and what is an outboard engine. Then we will learn the benefits and downsides of each of these engine types. We will also cover which one to get and we will give you our take. After, we are going to discuss some other topics and other good stuff. So, let’s get started.

What Is Outboard Engine?

An outboard engine is a boat engine that is mounted outside of the boat body. More precisely on the back stern of the boat.

There are many separated opinions on which design is the best but the outboard design is winning in the last few years with more and more people getting an outboard boat engine in comparison with inboard boat engines.

The outboard engine is placed outside of the boat, it is merely attached to the boat. This greatly improves the serviceability of this type of engine. This engine is also quite simple in design and it was built with boat use only in mind. But what does this mean?

This means that this engine could only be used on boats and nothing else. Since the propeller is mounted on the engine and they are one unit. While the inboard engine is a conversion. But more about these engines we are going to cover in the next chapter.

Since the engine and the propeller are a whole unit, you can just lift the engine and service the propeller if it needs servicing. Also, outboard engines are smaller and more compact compared to other types of engines. Making them extra popular because of this characteristic.

That’s why if you plan to run a smaller boat, getting yourself an outboard boat engine would be one of your top priorities. Since these engines are perfect for smaller boats.

But, you shouldn’t hurry and make your choice right away because we have a lot more to cover when it comes to outboard vs inboard engines. In the next chapter, we are going to learn what is an inboard engine and how do they work in practice.

What Is Inboard Engine?

An inboard engine is the opposite of the outboard design. In inboard boat engines, the engine or engines are mounted inside of the body of the boat. If you pay good attention at your local dock and see the boats parked there. You will notice how some boats do not have engines. But why is this the case?

This is the case because these engines are hidden inside the boat. They are not exposed like the outboard engines that some of the boats are running.

And you will also notice how these boats are quite bigger compared to the ones that are running inboard engines. These types of engines are used mostly by medium-sized or large size boats and yachts.

This is the case because these boats are designed with that philosophy in mind to hide the engines and make the boat look more stealthy and improve the boarding of passengers. Since when the boat is docked, it is quite difficult to board passengers if you have the engines at the stern like most outboard boat engines have their engines mounted.

The engines that these boats are running are engines that are “marinized”. But what does this mean? This means that these engines are automobile engines that are converted for boat use. One of the most popular engines out there is the LS family of engines, which are specifically converted for high-speed boat races.

That’s why if you want a boat with an engine that you want to customize and tune by yourself, then getting an inboard engine would be the way to go. But what are the pros and cons when it comes to outboard vs inboard engines? Well, we are going to cover that next.

Pros And Cons, Outboard Vs Inboard

Now it’s time to cover the pros and cons with both of these types of engines. Knowing the benefits and downsides is key in order for you to learn more about which type of engine should you get if you are on the market for a boat. This knowledge is going to save you thousands of dollars in the long run because not all engines are equal when it comes to purchasing and maintenance. But more about next. So, follow along.

Outboard Engine Pros

Let’s first see what are the outboard engines pros. The number one high point when it comes to outboard engines is the lower initial cost. Outboard engines cost considerably less when purchased out of the box compared to inboard engines. That’s why getting an outboard engine if you want to save some money could be a good idea.

Outboard engines have a higher cruising and top speed. If you plan to race a boat, then the outboard would be the way to go. Even though inboard engines will a little bit of tuning could even surpass the outboard engine when it comes to power.

You will have more space for activities. Since the engines are mounted on the outside, there would be more space on the inside of the boat that you could use to store objects or have more guests on board. This space you can use for adding extra features and other benefits.

Outboard VS Inboard

Outboards are lighter compared to inboard. More precisely 400 to 500 pounds lighter when compared to inboard which makes them extra fast.

Ease of repair is another benefit of running outboard engines. The engines are easily accessible and able to be repaired or replaced with great ease. In comparison to inboard where the removal is much more complex and costly.

They also offer a good service life of around 3,000 service hours before needing to be refurbished or replaced. Overall, then the outboard design is an excellent engine if you are planning to run a smaller boat, with these engines you will have all the versatility you need. But that doesn’t mean that they do not have downsides. And we are going to cover them in the next chapter.

Outboard Engine Cons

It doesn’t look particularly good. This con is not a performance issue but some people just don’t like the look of the onboard engines and think that they ruin the look of the boat. Even though modern designs have a lot more appealing designs compared to the early outboard engines that were used.

Poor boarding ability. Since the engines take most of the space in the rear, it’s a bit difficult to board people on the boat. That’s why some people also want to avoid these boats and get the inboard engine design instead.

Another con is the lower service life compared to inboard engines. Outboard engines last a bit less compared to inboard engines since they are smaller and exposed to more stress in comparison to the bigger inboard engine that has a long life.

Overall, these are the downsides, they are not a deal-breaker but could be a problem for some people. Next, we are going to cover the inboard engine pros and cons and learn which is the winner when it comes to outboard vs inboard.

Inboard Engine Pros

Now let’s discuss the inboard pros. Since both types of engines have their own pros and cons that need to be taken into consideration before purchasing a boat.

The first benefit of the inboard engines is the increased fuel efficiency. This is the case because, on inboard boats, you usually have one or two engines. On outboard, you start from one, and as the bigger, the boat is the engine number increases. For a big boat, you will need 4 engines to power this application. Which will add up significantly to your fuel bill.

But if you run only one outboard engine, then the outboard is a better investment. Since it is only one engine and is quite more economical than inboard application.

Another benefit of running an inboard engine is the engine life. Since the inboard engine is a bigger displacement engine means that it is considerably bigger and the internals of this engine last quite longer compared to an outboard engine. These engines easily last more than 6000 hours which is double the amount compared to the outboard engine.

On inboard boats, the engine is mounted low and is centered. Which translates into easier maneuvering at higher speeds.

Inboard Engine Cons

But there are significant cons when getting an engine of this type. So, which are the cons? Let’s find out.

The first and the biggest con when getting an inboard engine is the initial cost of the engine. These engines cost considerably more compared to outboard engines. This can result in a few grand more spent on an engine compared to the alternative.

The second point is the lower top speed. Inboard engines are not that powerful compared to outboard engines. This is owed to the fact that they are not boosted and are not made to be performance machines. Even though, the aftermarket is quite big when it comes to upgrading these engines and making them produce a ton of power. That’s why you shouldn’t worry if your engine is low on power because you will be able to upgrade it with a new one or boost the existing engine.

Another con is the size of the engine. These engines as we mentioned are considerably bigger and take a lot of space. So, you can expect that with this engine you will face some space issues. The engine compartment is quite big and could steal some valuable space that you could use for storing fishing equipment or bringing some guests on the boat.

Complex maintenance is another big problem with this type of engine. They are quite more complex in design and require some professional maintenance. Also, in order to repair an engine, you will have to remove it from the boat. Which can take a considerable amount of time and money to perform.

The last con is the considerable amount of spray that this engine makes while running. Overall, these engines are quite more expensive to maintain and own.

Performance Outboard Vs Inboard

Performance is an interesting topic that we would like to cover since performance is the most important what you can expect from a boat along with usability.

In the past, outboard engines were only two-stroke and were extremely down on power compared to inboard engines that are beefier engines. But since recently there was a switch from 2-stroke to 4-stroke. This brought the outboard engines up to the spec of inboard engines.

Inboard engines are producing from 10 hp up to 600 hp. Which is pretty insane, to be honest. And you can mount even up to 5 of these at the rear. Imagine 5 times 600 equals 3000 hp with no problem. And these engines are also fairly quick, achieving 50 mph with no problem.

Outboard VS Inboard

But if you want to go a step further in performance, then an inboard engine would be the way to go. Inboard engines are all about performance and power delivery.

That’s why you will often see them on towboats, expensive yachts, and speed boats. They can be tweaked to deliver excellent performance. Since they are car engines at their core.

There are a ton of companies out there that are making these types of engines for boat racing and offer components with which you can upgrade your existing engines. And even fully built crate motors that you can just install in your boat and go to speed boat racing.

There are many variables when it comes to both of these engines when it comes to performance and that’s why it is quite tricky to choose which is better. But my vote would go for the inboard engine. Because these engines are much bigger and more reliable in comparison to outboard engines.

Maintenance And Costs

As we mentioned, the costs for both of these types of engines can vary from the horsepower rating as well to the application they are intended to be installed in.

The inboard has a more expensive initial cost. This means that this engine is quite more expensive to purchase in comparison to outboard engines.

The inboard engine also has a higher cost when it comes to maintenance. This engine is inboard which means that this engine is inside of the boat. So, to service, this engine could be a bit tricky.

When doing serious maintenance like replacing engine components. The whole engine has to be removed from the boat altogether. This removal will cost quite more in comparison to the outboard engine. The labor can cost you thousands of dollars extra when it comes to the maintenance of inboard engines.

That’s why you need to pay close attention to this and make your purchase based on this information.

Outboard engines on the other hand are quite cheaper to maintain because they are easily removable from the boat. This greatly reduces maintenance costs in the long run.

Considering these facts, the outboard vs inboard battle win goes for the outboard type of engine when it comes to the overall cost and ease of use.

So, if you have a limited budget, then you should opt for the outboard engine. Else, go for the inboard type of engine. But in the next chapter, we will give our final verdict when it comes to outboard vs inboard engines where we will sum up all of the positives and negatives and draw a conclusion.

Which One To Get, Outboard Vs Inboard?

Now it’s time to give our verdict on which engine you should get for your future boat, outboard vs inboard? Hmm, let’s see…

As we mentioned. Both these engines have their pros and cons and also their own applications. Because although they are boat engines, they are quite different in terms of the performance that they deliver.

Outboard engines are extremely practical and the ease of maintenance makes them highly sought-after on the market. Considering that modern outboard engines are making similar power to inboard engines is astonishing because not until recently they were running only on 2 strokes and performed poorly. But not anymore. Modern outboard engines are the way to go.

But the key is the application that you want to use these engines for. For example, if you plan to tow a lot or run a bigger boat or small yacht. Then outboard engines are not going to cut it. You will have to mount a few of them and the end cost will add up fairly quickly.

That’s why getting an inboard engine if you plan to use a big boat is a much better option. These engines are quite more reliable and also more durable in comparison to outboard engines. But they also cost significantly more.

The second important aspect is the cost of ownership and maintenance. Inboard engines cost to purchase quite more and also quite more to maintain. So, bear this in mind.

Now to sum things up. If you want to use the engine on a bigger boat or use the engine for a speed boat then go for the inboard option. If you plan to use it on a smaller fishing boat, then go for the outboard option.

Can I Make An Engine Conversion?

Yes, you can make an engine conversion. You can get a truck or car engine and you can convert it into a boat engine. This process is also called “marinizing”.

The term “marinizing” means that the company that is building these engines (or yourself if you get a conversion kit) adds the integral peripheral components that make this engine marine-worthy.

Because you cannot install an engine into a boat just like that. These engines go through a long process until they are fully prepared to serve into a boat and many of the components are swapped in order to make them perform up to the task of running a boat.

Luckily, there are a ton of conversion kits on the market for popular engine applications. Let’s take for example the LS family of engines by Chevy. These engines are enjoying huge popularity and parts are readily available when it comes to converting these engines into boat engines. There are also a ton of other engines that could be a good boat engine and it’s up to you to do your own research and learn more about these conversions.

Boat Engines: Inboard vs Outboard – Facts

  1. When buying a boat, you need to budget for an engine as they are sold separately.
  2. There are two types of boat engines: inboard and outboard.
  3. Inboard engines are inside the hull of the boat and connected to a driveshaft while outboard engines are mounted on the outside of the boat.
  4. Inboard engines are either true inboards or inboard/outboards (I/O) while outboards are fully outside the boat.
  5. True inboards are placed in the center of the boat and have a separate rudder for steering while I/O engines are towards the back and have a propeller that steers the boat.
  6. Outboard engines can be removed for storage and can lift up to avoid shallow water or obstacles.
  7. Inboard engines are more common on bowriders, ski boats, and midsize to larger cruiser boats.
  8. Outboard engines are more common on pontoons, aluminum boats, bass boats, bowriders, small cruisers, and some high-performance speed and fishing boats.
  9. Inboard engines cost anywhere from $8,000 to $25,000, while outboard engines can cost from $1,000 to $15,000+.
  10. The choice between inboard and outboard engines ultimately comes down to personal preference and the type of boating activities you want to do.

Conclusion – Outboard Vs Inboard

In this article, we have covered a lot when it comes to outboard vs inboard engines for boats. We learned what are these engines and how do they differentiate from each other.

Then we have covered the pros and cons for each of these engines. Both these engines have their own pros and cons and based on these pros and cons you should make your decision.

Lastly, we have shared our opinion when it comes to choosing an engine for your application. And we also shared our thoughts on converting a regular automobile engine into an inboard boat engine.

You may also like

Leave a Comment