Why Boat Engines are Unreliable
Your boat may sometimes seem like a money pit that leaves you wondering if it is worth the expense and energy. Although most boats may seem unreliable, there are plenty of boat engines that work quite well and last boaters for years or even decades. But have you ever wondered why some engines seem less reliable than others?
Why Boat Engines are Unreliable
Why are boat engines unreliable? Many boat engines are “unreliable” because they are not taken care of correctly. While some boat engines are less reliable than others, there are common engine issues that appear from overuse, ill-maintenance, or low-quality materials. An engine can and should last you for an average of 5,000 miles, but only with proper care and long-term investment.
Owning a boat can be an overwhelming undertaking, but it can result in fun memories that last a lifetime.
If you want to be enjoying the waves and the wind in your face for a long time, you must educate yourself on how to care for your boat engine.
This article will discuss the life expectancy of most boat engines, common issues, and how you can be a more knowledgeable boat owner.
Life Expectancy of Most Boat Engines
As Boat Safe describes it, “The average marine gasoline engine runs for 1,500 hours before needing a major overhaul. The average marine diesel engine will run for more than three times that long and log an average 5,000 hours under the same conditions.”
The four different types of marine engines are:
| Type of Engine | Description |
| Outboard Engine | Outboard engines have become the go to engine today for most personal boats. Its the engine you see mounted to the back of a boat. Used to power the boat and steerSelf-contained |
| Inboard Engine | Located inside the boat and connects to a shaft that turns the propellers for movement. Similar to automotive engines not responsible for steering the boat. |
| Stern Drive | Also known as the ‘Inboard-Outboard’ Engine because it is a combination of the two. More Fuel-efficient and typically quieter than an inboard engine. It powers as well as steers the boat but uses a ‘drive unit’ to do so. |
| Jet Drive Engine | Uses a water pump to eject the water backward, which propels the boat forward. Mostly used for personal watercraft or jet-skis. May have either inboard or outboard jets. |
Of course, the longevity of your engine will depend on the:
- Type of engine
- Number of gears
- How well you maintain your boat
- Its purpose (saltwater, freshwater, shallow waters, etc.) and if it is used according to that specific purpose
Other things which may affect the longevity and reliability of your engine include:
- How rough you are with the boat
- How fast you drive the boat
- How hard you are pushing the engine
- How well you maintain the oil levels
Part of why your boat engine isn’t lasting as long as it should or running as well as it should be because of the number of gears the engine has is inadequate for the weight it is propelling forwards. If a boat doesn’t have a proper gear setting or enough strength to carry the vessel it’s attached to, it will often give out prematurely or cause the boat owner many costly issues and require many repairs.
However, if you use the right boat engine for the proper intention with adequate maintenance, your boat should last you for decades.
Common Reasons Boat Engines Blow Out
You don’t want to be left adrift in the middle of the ocean. It is essential to maintain your engine correctly, or you could be left stranded without a clue of what to do next.
Some of the commons problems your engine can have and what you as a responsible boat owner need to watch out for include the following:
- Your fuel went bad – If you don’t drive your boat often or get it out of the harbor for long durations between boating trips, you may cause condensation to build up in your engine. This can even happen while taking a single season off.
- The solution – Consider adding fuel stabilizer [article] to your tank when you plan to take a long break. Add this to your tank each time you add fuel, and it will help to minimize condensation and will extend the life of your boat engine.
- Your Engine is Overheating – Many things cause this, but it could be something trapped between the gears or pullies that is causing the entire engine to overwork itself. If the temperature gauge is alerting you of a rise in temperature, it could mean that water is not circulating throughout the engine to cool things internally.
Solution – Check the engine for anything foreign that is caught in the engine. It could be as simple as a twig, weed, or water pollution that has clogged your engine. Be sure everything is turned off and pull it out just as you would pull a paper jam out of a printer.
- Your drive belt may be broken – Your check engine light may turn on or a voltage meter could alert you, but you most likely will not be able to hear the drive belt snap audibly.
Solution – Always carry a spare along with a toolbox to switch it out.
More boat engine issues to be aware of are:
- Your spark plugs are worn and need replacing.
- Your air filters are clogged and causing overheating.
- The fuel lines might be kinked or damaged.
- The compressor is leaking.
- The compression is too low overall, which could be caused by a variety of issues.
How Long Should Your Boat Engine Last You?
Ultimately, your boat engine should easily last you for ten years.
For example – If your boat will last for 5,000 hours (with a few repairs here and there). This would equal 500 hours per year, 41 hours of boating each month, and 10 hours per week.
Most people do not have time to boat for 10 hours per week. So this figure is quite generous, even for a heavily-active boater.
Your boat should last you for double or even triple this amount of time. Some boat owners have had the same boat engine for 50 years!
It will all come down to how well the boat is maintained, how knowledgeable the boat owner is about catching issues, and how quickly they act when they notice a problem.
Learn More: Why are boat engines measured in hours?
Final Tips for Boat Owners
Some parting words to get the most life out of your engine and have a reliable boat you can depend on are:
- Rule number one: Always fill the tank before leaving the marina!
- Examine your boat each time before taking it out to avoid being stranded. There could be a quick fix or tank to fill before you depart the harbor.
- If you live in a saltwater area that will add salt-corrosion and weigh on your engine, scrape the salt corrosion off seasonally to avoid a buildup that could stall your boat engine.
- Do not try to haul heavier loads in the boat than your model is made for. This strains the engine too heavily and can cause long-term damage or even result in a replacement being required.
Your boat engine is just like a car engine and will require the same amount of annual maintenance and upkeep from you as any engine would.
It is recommended that all boat owners do the following:
- Research the specific maintenance for your boat model – read the user’s manual, watch tutorials, and get to know the boat that you’ve purchased.
- Learn more about your specific engine type and what it needs to thrive (Outboard Engine, Inboard Engine, Stern Drive, or Jet Drive Engine).
- Understand how your boat gets worn down by specific water environments.
- Boats have a shorter life expectancy in saltwater, so be aware of this before purchase. If you are boating in saltwater, learn how to protect your boat from salt corrosion, barnacles, rust, and more.
- If in freshwater, you will have fewer issues and a longer life expectancy on your boat and engine.
In Conclusion
When it comes to the reliability of a boat engine, the responsibility of maintenance and upkeep to extend the engine’s life falls entirely on the boat owner. Be aware of the things that can make your engine degrade more quickly – like boating in saltwater and using an engine that is not powerful enough for your boat. If you do your research and learn your boat inside and out, it will last you for years!