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Can You Change an Inboard Boat to an Outboard?

Sunset view at the harbor.

As you might have guessed, yes, you can change an inboard boat for an outboard one. This can be done in either two steps or one step, depending on the method you prefer to use and how much work you want to put into it. This guide will go over both methods in detail so that you can make the best decision on how to change your boat from inboard to outboard.

Difference Between an Inboard Motor and an Outbound Motor

Modern motor boat drifting at the ocean.

Inboard/outboard refers to whether a boat’s engine is mounted inside or outside of its hull. Inboard motors have smaller motors that are able to fit entirely inside of a boat and can be easily repaired or replaced.

Outboards, on the other hand, have larger motors that stick out of their hulls, making them more expensive but offering greater space for storage. Because inboards are typically smaller than outboards, they’re better for small boats with low storage capacities.

Is Inboard to Outboard Conversion Possible?

Old inboard motor board under maintenance.

The answer depends on the make and model of your boat, but for the most part, the simple answer is yes. The process can be costly, but if you are willing to spend the money, it can be done.

You will need to make sure that your boat is strong enough for the motor and properly weighted as well. A strong hull can withstand a larger motor than a weak one. Also, make sure that any equipment (such as your fuel tank) is located below the deck so it doesn’t cause any problems once everything is hooked up correctly.

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The most important thing when doing any conversion of your motor system is safety. Make sure that all wires are properly connected and double-check that there are no fuel leaks or other issues with your installation before taking it out into open water.

Is it Worth it to Change an Inboard Boat to an Outboard?

Three new outboard engines.

Removing the inboard motor will change the weight distribution of the boat and may require some reconfiguration of deck hardware. It will also allow for extra storage in the engine area, which can be beneficial on boats with limited space in that area.

If you’re unsure whether or not it’s worth it, consult your dealer or manufacturer. You may even find a solution from a third-party company if your boat is no longer made.

How Much Does it Cost?

Many people think that changing from an inboard to an outboard engine is as simple as swapping out one for another, but it’s actually not. In most cases, it requires extensive work to accommodate different water pumps and components.

The average price tag is $30,000 to $40,000, including parts and labor. Additionally, since most propane tanks are buried deep inside marine engines, it means more hours of labor and replacement costs if your tank or hose ever breaks.

An added cost comes with any modifications that need to be made, such as adding battery boxes and such. The other consideration is where your engine will go. The location of your engine is not always straightforward, so finding places to mount it may cost more money as well.

Inboard Motor Advantages

Powerful inboard motor boat on a boat trailer.

More Short Term Power

Getting a flatwater powerboat is all about having fun, not just going fast. If having lots of horsepower—for acceleration and towing capacity—is important, then an inboard engine is better than an outboard because it delivers more short-term power from a smaller package.

This can be especially true if your boat has only one or two seats instead of four or five. In that case, every pound of engine weight reduces your cruising range and top speed by roughly 1 mph.

Inboard Motors Sound Better

There’s a reason so many boaters choose to take their craft out for a spin on a lake or downriver. If I were writing about how to choose an engine, I might dive into specific horsepower ratings and fuel efficiency and how those matter more than anything else—but what I really want to talk about is sound.

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If you have your heart set on a certain type of boat, it’s worth considering how much noise and vibration might bother you—but don’t let that stop you from getting what will make your boating experience more enjoyable.

For example, many people prefer a deep rumble when they want to get going. Other people would rather be completely immersed in their surroundings and prefer complete silence. For example, some boats have upgraded soundproofing that can reduce vibration and make for a more pleasant ride.

Disadvantages of Inboard Motors

Old inboard stern drive with cracked seal.

Inboard Motors Are Less Efficient Than Outboard Motors

Inboard motors are always less efficient than outboard, no matter how efficiently they’re designed or how much energy is used. They take up more space and require a lot of maintenance, too.

An outboard motor has fewer moving parts and can be stored outside of your boat. You can also choose from a wide variety of models with different horsepower levels and features that will work well for your particular needs. If you want a more powerful engine on your small fishing boat, then an outboard is definitely going to be your best bet.

It’s Harder to Do Maintenance On an Inboard Motor Than an Outboard

It’s often a lot harder to perform maintenance on an inboard motor than it is on an outboard. Most of us have only a vague understanding of how our boats’ engines work, but no matter how good your mechanic is, he or she can’t do much for you if they can’t find what needs fixing.

An outboard motor is usually pretty easy to get at because it has fewer parts and less complex moving parts. Having more access points makes it easier for people with less mechanical knowledge to work on their own craft. It’s also just as important that these areas be accessible should a professional need them—to facilitate easier repairs, etc.

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Inboard Motors Are Harder to Clean Than Outboards

An inboard motor contains additional components, such as a fuel filter, fuel pump, and carburetor. In order to access these pieces for cleaning and maintenance, several other parts need to be removed first.

While an outboard engine can be disassembled quickly and easily, it’s not nearly as simple as an inboard engine. That’s why if your boat needs a major cleanup or tune-up that requires all the parts inside of your engine to be removed at once (like after months at sea), it’s best to have your mechanic perform such tasks rather than try doing them yourself.

These professionals are experienced with handling engines of all sizes and should be able to complete all necessary steps much faster than you would on your own.

How Long Can an Inboard Motor Last?

Modern inbound motor boat with a blue ceiling.

Depending on whether your engine is 4-stroke or 2-stroke, it can last between 1950 and 2930 hours.  However, if you want to change from an inboard, outboards are far more expensive than most other types of engines, but there are other ways around it.

Many people go with small electric motors, which can be as cheap as $300 and stored inside a compartment when not in use, making them ideal for weekend excursions. Skipping across shallow water is hard on motors of any kind, so make sure yours is designed for that purpose!

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So Which One is Better, an Inboard or an Outboard Motor?

White yachts and modern motor boats at the harbor.

Outboards are more powerful and fuel-efficient in the long run. Outboards also put more power on the water, which is what makes them ideal for boats that need extra muscle.

Inboards are easier to use, cheaper to repair, and can handle rough seas better than their alternatives. Since the engine’s exposed, it’s easier for beginners to get the hang of shifting gears; those engines typically have only two or three controls (throttle, clutch, and reverse gear).

However, they aren’t as strong and have more moving parts, so it’s easy for things to break down when they’re not well-maintained.

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