How Long Do Boat Motors Last? Average Numbers (8 Popular Brands)

Before buying a boat, you might be concerned about how long the boat’s motor will last. A motorboat is worth nothing without its engine.

How Long Do Boat Motors Last?
Boat motors typically last at least 2,000-3,000 hours before they need serious maintenance. Inboard motors will sometimes last longer because they are more protected from wear and tear. 

Here’s everything you need to know about how long boat motors last.

The engine condition is also a big factor when it comes to your boat’s value. If you plan to resell, your vessel’s value will drop if the potential buyer also has to pay for a replacement engine.

An engine’s weight and horsepower can impact the performance and the longevity of your motor.

Motor Types And Their Lifespan:

There are many different motor types and motor manufacturers. Different types of motors can offer different advantages and disadvantages.

Below, I have listed the different types of motors and their specifics.

One thing to note for any motor type is that regular maintenance can extend the lifespan of your motor.

Gasoline Versus Diesel:

Diesel engines often last longer than gasoline engines. This is because when engines operate at a higher speed, they have fewer revolutions.

Faster engines can even revolve 1/3 of the times that slower engines do. This means less wear on the engine itself and allows for longer use.

Diesel also includes oil which means that it has fuel for combustion and lubrication. This also allows for less wear on the engine.

An engine’s lifespan depends on how much fuel has been burned and diesel has less pure fuel that burns. Gasoline is only combustible fuel so diesel engines burn less fuel per mile.

Average Lifespan Of 4 Outboard Motor Brands:

An outboard motor is one that is mounted on the boat’s stern, outside the hull. This type of motor has both its gearcase and propeller submerged during operation.

This motor can then be tilted out of the water when not in use. Tilting your motor out of the water can prevent unnecessary corrosion or marine growth.

This can make outboard motors ideal for salt or freshwater use. This also allows for easier storage.

Outboard motors are also easier to replace when necessary because they are mounted to the ship, not built into it. They are also easier to service so they have a reputation for being more reliable.

Outboard motors allow for easier maneuverability at lower speeds and can make docking your vessel easier.

A large drawback is that they are less powerful and you might need a bigger one or even more than one motor to get the desired performance.

Having more than one motor will take up space and make your boat heavier.

When buying an outboard motor know that they come with their own cost that is not likely built into the price of the boat and they will often need to be listed separately on your insurance policy.

1. Evinrude Outboard Motors:

Evinrude is a major brand of outboard motors. These engines are two-stroke direct-injected engines.

The horsepower for these engines ranges from 25 to 300 hp.

Evinrude Motors pride themselves on being fuel-efficient as well as reducing noise, oil usage, emissions, and maintenance needs.

Two-stroke outboard motors can reasonably live between 1,500 to 2,000 hours before needing major maintenance. It can last even more with proper maintenance and preventative measures.

2. Honda Motors:

Honda Motors are outboard motors with horsepower ranging between 2 to 250 hp.

Honda engines are known for their reliability and confidently offer a 5-year manufacturer’s warranty.

Honda motors don’t skimp on materials or their finish. They hold their motors to high standards and have won the National Marine Manufacturers Association CSI award fifteen years in a row.

These motors are often four-stroke. Four-stroke motors boast lower operating costs, are more environmentally responsible, and are generally quieter than two-stroke engines.

These motors can run over 2,000 hours before looking into major repairs. Even longer with proper maintenance.

3. Mercury Marine Engines:

Mercury Marine Engines offer a wide variety of outboard motors. These motors can range anywhere from 2.5 to 400 hp.

These are most commonly gas-powered four-stroke engines.

Mercury motors are water-cooled with a thermostat and are also pressure controlled. This can help to increase the longevity of your motor.

Mercury outboard motors offer adaptive speed control, available active trims, and even a joystick for piloting.

Mercury motors claim to last thousands of miles, but like all other motors, this depends on the care, maintenance and use put into it.

With the proper care and cleaning Mercury outboard motors could offer you over 2,000 or even 3,000 hours of use.

4. Suzuki Marine Motor:

Suzuki offers high-output, lightweight, four-stroke, outboard engines. Suzuki engines offer a range of horsepower between 2.5 and 350 hp.

They offer twenty different models of the outboard engine which means you are bound to find one that fits your needs and your vessel.

Suzuki is a national motor company that continues to strive for more power, more fuel efficiency, and reduced noise for their motors.

With a high emphasis placed on integrity, Suzuki builds their motors to last.

Like other outboard motors, you can expect a lifespan between 1,500 to 2,000 or more.

Average Lifespan Of 4 Inboard Motor Brands

An inboard motor is one where the engine is mounted within the hull of the boat and is often under the deck.

This motor type has a drive shaft with a propeller mounted on it that extends through the hull.

Steering with this engine type is accomplished by using a rudder.

These motors have a low center of gravity and create a smaller wake. They are also quieter.

The inboard motor is also more fuel-efficient, they also generally have better horsepower and more torque.

They are, however, more expensive than an outboard motor and they take up more cabin space to allow for the motor inside the hull.

Inboard motors are harder to steer if you are not applying thrust, which can make docking more difficult. You can equip them with a joystick control to enhance maneuverability without thrust but that can be expensive.

If not properly ventilated, the inboard motor can also cause a fire.

5. Crusader Engines:

Crusader Engines are inboard motors that pride themselves on their exclusive and highly developed features.

The horsepower for Crusader Engines can range from 275 to 425 hp.

The Crusader Engine uses a modular water pump and a freshwater system to cool the engine block as well as the manifolds.

This cooling system helps to enhance the durability and longevity of the engine.

They have also designed a better mounting system, work on fuel efficiency, and clean emissions.

These motors will last between 2,000 and 2,500 hours if properly taken care of and is never run on low oil levels.

6. Ilmor Inboard Marine Series:

The Ilmor motor series is ideal for competitive water sports as well as recreational boating. They are known for their power and speed.

They are held to high standards and are high performing and reliable.

Ilmor is so confident in their motors that they offer a 7-year/1,000 hour factory-based Standard Limited Warranty.

These motors feature gasoline direct injection, temperature control, easy access to fuses, emission reduction, corrosion protection, easy service, quiet performance, a smooth ride, and a longer lifespan.

The Ilmor motor offers motors with horsepower over 500 hp.

These motors will also last between 2,000 and 2,500 hours. You will also have peace of mind with a 1,000-hour warranty.

7. MAN Engines:

MAN Engines build efficient engines that can use either diesel or gas. These engines range in horsepower from 50 to 2,000 hp.

They have one of the most diverse product lines offered. They also are compact in size. They also allow for low fuel consumption.

After installation, these engines come with a guarantee and a Gold Standard Certificate.

These engines comply with all exhaust-gas regulations.

The lifespan of these engines varies widely depending on whether you get the gasoline or diesel option. Diesel can last 1,000 or more hours longer than a gasoline engine with the proper maintenance and attention.

This means the MAN Engines can last anywhere from 1,500 hours to over 4,000 hours.

8. Yamaha:

Yamaha is a highly diverse company that can offer you anything from outboard motors, inboard motors, even the boat itself.

The benefit of this is that with Yamaha you can purchase everything from one company. This is helpful to know that your equipment is compatible and has been all been built with the same amount of care and attention.

They pride themselves on performance and durability in every market they are a part of.

The reliability of Yamaha’s motors will vary depending on which motor you choose. Because they offer both inboard and outboard they could have a lifespan that ranges from 1,500 to over 3,000 hours.

What is Considered an Average Amount of Hours (Per Year)?

The average use for a recreational boater is about 50 hours per season. When estimating hours on a used boat, or motor, you will want to estimate around 50 hours per year.

This can change depending on the owner’s location. A place where the boating season lasts longer can mean more hours on the motor.

This means that a motor that lasts even 1,000 hours can last 20 years with the proper maintenance as long as you do not ride it too hard.

But how can you know how many miles are actually on a motor?

If a boat has electronic fuel injection, you can look in the engine management system. This will give you a reliable record of the engine hours.

An accurate representation of engine hours can be very important if you are planning on buying a used motor.

Boat Hours versus Miles:

Boat hours generally translate to between 50 to 60 miles per one hour of use. This does not mean that your boat travels 50 to 60 miles per hour, but instead looks at a variety of factors.

When calculating miles on a car, it is simply the miles that have been traveled, but for a boat, it is much different.

When calculating boating hours to miles, you need to take into account the strain on the engine.

Because of water displacement and having to fight against the waves and the wind, boat engines work much harder than engines that are used on land. This is why you allow for extra miles on your marine engine.

If you consider the average boating season yields 50 hours on your motor then you would be adding the equivalent of 2,500 to 3,000 miles onto your engine. This is often why an oil change is recommended every season or even sooner with greater use.

3 Tips For Picking a Motor That Will Last Long

Often, when you are picking a motor for your boat, you will be looking at an outboard motor.

This is because inboard motors often come equipped with the boat you are purchasing. If you purchase a new boat, you might be able to upgrade your inboard motor to a higher horsepower or nicer model, but otherwise, you will get what is already equipped.

You can replace an inboard motor, but it is expensive and might not be immediately necessary.

There are a few factors to consider when picking an outboard motor.

1) Choose The Right Size

Choosing the size of your motor is simple, but important.

Your boat should have a capacity plate, or recommendation, for motor size, appropriate horsepower, and total weight limit for your vessel.

If you equip your vessel with too much horsepower you can tip your boat and sink motor-first.

You also don’t need to choose the maximum horsepower for your boat. The higher the horsepower, the more expensive the motor.

If you do not need the horsepower, you can save yourself some money by opting for a lower horsepower option.

A lower horsepower motor can also use fuel more efficiently.

The weight of your motor is also important when deciding which one to buy and equip.

2) Choose The Proper Shaft Length

You will need to have a shaft length that is the proper size for your vessel.

The shaft length should match the height of the back of your boat. You should measure from the bottom to the top in the middle of the stern.

An inch or so of a difference is not a big deal, but you will want to make sure you are as close as you need to be.

Failing to choose the right shaft length may impact how long your motor will last as it might wear it out too quickly.

You can also look for outboard motors that have the ability to tilt in and out of the water.

3) Gasoline or Diesel?

Another consideration to make is whether or not you want a gas or diesel motor.

Both gasoline and diesel motors can be either outboard or inboard, but there are other considerations to make.

As mentioned above, diesel engines generally last longer and have a higher lifespan than gasoline engines. Diesel engines generally run for a couple thousand more hours than their gasoline counterparts.

Diesel engines also generally have more horsepower than the typical gasoline engine. They are also more efficient due to the content of the fuel.

Diesel engines, however, are more expensive and heavier than gasoline engines. They are also louder than diesel engines.

It is not necessary to have a diesel engine for your vessel. Despite the higher horsepower and additional longevity, getting a diesel engine is not always what is needed.

Gasoline engines are getting better every year and their lifespan is continuing to grow. They are also making great strides in reducing emissions and making them more fuel-efficient.

Your boat also might not need the amount of horsepower a diesel engine provides and you should not buy a motor with more horsepower than your boat can handle. Not only will it be more expensive but it can cause great risk for your boat, your motor, and even your passengers.

Should I Get A Used Motor?

If you are looking to purchase a used motor, there are some things that you want to look for.

First things first, you want the motor to be clean. If the motor is not clean, it is safe to assume the previous owner did not properly take care of it.

You also want to pay special attention to gunk or grime deposits. Not only do these indicate motor neglect, but could also be evidence of ethanol contamination on a gas-powered engine.

Most fuels that are made today use some amount of ethanol in them. Marine engines are generally not designed to run on this type of fuel and non-ethanol marine fuels are not always available.

As a boat owner, you will want to make sure if you are not buying ethanol-free fuel, that you are adding the proper additives to lessen any possible ethanol problems.

You also want to test the used motor and make sure every aspect is in working order. Check for signs of smoke, excessive noise, or vibrations.

How to Prolong The Life Of Your Boat Motor

How long an engine lasts is hard to accurately predict. There are many variables that can affect engine life.

One major factor in engine life is whether or not the engine uses diesel or gas.

To keep your engine from wearing out you will need to make sure you change the oil at the proper intervals. Make sure you check the manufacturer’s recommendation. This recommends oil changes for standard use.

If you are traveling and you have an unusually heavy load, dirty air, or high temperatures you will want to consider changing the oil more often. If this is not the case, there is no benefit to changing your oil more often than is recommended.

Rough operation techniques can include extended low-speed operation, incomplete burning of fuel, or incredibly heavy loads.

You can also consider synthetic oil. Synthetic oil often lowers wear rates compared to petroleum oil. It is hard to say if this extends life, or by how much, but it could help.

If you keep your boat somewhere where the weather gets cold, you should drain and refill the oil before the boat is winterized.

When you go to start your boat back up in the spring, you will want to make sure you let the engine idle to recirculate the oil. Since the oil has probably settled, you will need the oil circulated back through the system.

If you do not do this, you could add enough wear in your first journey out as you would add all year.

When you change the oil, make sure you change the filter as well. You should keep track of the date you change the oil and filter so you know when you need to do it next.

You can also try to motor at the most efficient cruising speed for your vessel and motor. This will burn the least amount of fuel which can extend engine life.

Considerations About Salt Water Exposure

No matter what type of engine, the components inside can be at risk with saltwater exposure.

Saltwater can cause corrosion in metal. This can be combatted by inspecting your engine for corrosion regularly. When you find corrosion, you will want to deal with it immediately.

This should be looked at monthly.

To deal with corrosion, you will need to remove it down to the bare and base metal. After this, prime the area and paint it with manufacturer-approved paint.

Like rust and other issues, the earlier it is caught, the better off you are. If you do not find it in time, you will have to replace the component. This can be more expensive than simply dealing with the corrosion.

We have an in-depth article here with some things you need to know before you take your boat out in saltwater.

One area to make sure you check properly is the exhaust elbow. This is where the water leaves the engine block but also where the exhaust gases also leave. If the exhaust elbow fails you could be looking at an issue that can vary from a messy leak to engine overheating.

Preventative maintenance is also a key factor in engine life. Preventative maintenance means to replace or repair things before they are needed.

Some people go by the “if it isn’t broke, don’t fix it” strategy, but this can cause issues later that could be more expensive.

At the very least you should get regular inspections and constantly check your engine’s components.

Important Dangers of Overheating Your Boat Engine

Overheating is a major threat to your engine’s longevity.

Overheating is when the internal temperature of the motor raises to dangerous levels.

Overheating can deform the internal components due to the extra heat. This can cause the internal components to need to be replaced or even the entire engine.

Minimizing or avoiding your engine overheating can increase your engine’s longevity.

To reduce overheating you should replace your coolant when recommended. You should also replace your engine’s sacrificial anodes.

You will also want to make sure you inspect your raw-water strainers.

While you are underway, you will want to make sure you keep an eye on your gauges. Keep an eye on your temperature gauge while out.

You will also want to make sure your engine alarm system is operating as it should be. This will alert you to any possible problems with your engine.

If your alarm does go off you will want to make sure you reduce your engine speed or possibly shut the engine down completely.

If you continue to run your engine on high temperatures, you can cause internal damage to your engine. This might not be visible right away, but you will notice this damage in the long term.

Every instance of overheating should be treated as a reduction on your engine’s lifespan.

Monitoring Your Exhaust

Marine engine builders recommend that engine compartments get dry, cool, and clean air while running.

Your engine compartment blowers should always be set to exhaust and never be set to blow air in.

You should also run your engine compartment blowers for at least 5 minutes before you start your engine. This allows your engine to run in clean air at all times.

You should also keep an eye on your exhaust. If your exhaust does not run clear you will want to know why.

Some possible causes of colored smoke include:

  • Black smoke:
    likely the result of an overload on your engine, a restricted air supply, or for diesel engines a malfunctioning fuel injector.
  • Blue smoke:
    caused by combustion of your engine’s lubricating oil. Can be caused by worn piston rings, valve guides, or oil seals. If you have a diesel engine you could have an overfilled air filter or excess oil in the crankcase.
  • White smoke:
    possibilities include water vapor from dirty fuel, a water leak into the cylinder, air in the fuel, or completely unburned fuel.

If you notice any color of smoke you will want to locate the source of the issue and take care of it immediately.

In Conclusion:

Overall, what type of motor you choose to purchase for your vessel is completely up to you, your needs, and the needs of your vessel.

Make sure when you choose you carefully consider your options including gas or diesel, inboard or outboard, as well as size and horsepower.

Ensure that you treat your motor properly and take care of it. Do not allow small issues to escalate because this might just mean replacing the whole thing, and that can get expensive.

No matter what type of motor you get, you should be prepared that it will not last forever. However, with the proper maintenance and preventative techniques, you can increase the lifespan of your boat’s motor and preserve the value of your vessel.

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