outboard power

Some luxury motor yachts have outboard motors, others have other means of propulsion. However, even if your motor yacht is not equipped with outboard motors, your tender probably is. So, any motor yacht owner really needs to be aware of the problems with outboards that can cause them to fail to start, or not run as smoothly as they should.

Today’s outboard engines are much more sophisticated machines than they once were, featuring some very complex components. However, they still pretty much fail for the usual reasons. Here are some of the most common issues you are likely to face with an outboard motor.

Electrical Issues

If an outboard engine won’t start, an electrical problem is high on the list of the probable reasons why. It could be something as simple as a dead battery. The good news is, even if you are off in some exotic locale, and ready to take your tender to shore, most of the time, an electrical problem can be easily traced, and easily fixed. If your battery is charged, check that the throttle is in the right position, and that all the connections to the battery are tight and free from corrosion.

yacht engine repair

Fuel Flow

The next most common reason that an outboard motor won’t start, or sputters to stop at a most inopportune moment, is a problem with the fuel flow. And, just like a dead battery, what do you think is the most common (and preventable) cause of a fuel flow problem? NO GAS! Marine fuel gauges can be unreliable; make sure your tanks are topped off before you leave the dock!

Other problems with fuel flow may not be so simple to fix. You could have a blocked or leaky fuel line. Clogged filters or fuel/water separators can also prevent fuel from getting to the engine.

Fill ‘er up at FYM!


Temperature Problems

An engine’s cooling system is next on our list of the “usual suspects” when you have a problem. Your outboard is water cooled. The cooling water drains from the “telltale.” Even if your engine appears to be running smoothly, if you do not see a constant flow of water from the telltale valve, you’ve got a problem. If there is normal water flow from the telltale, and your temperature warning light goes off, or before it does, your engine conks out due to overheating, it may be as simple as clogged intakes. After that, an overheating engine can be caused by more serious events, such as a damaged or defective impeller, or a problem with the oil pump.

 overheating boat engine 

Pings, Knocks and Other Mysterious Sounds

After not starting, or overheating, or otherwise not running correctly, the next problem you are likely to encounter with an outboard engine, is vibrations and/or other strange sounds. If something does not “sound right” when your engine is running, trust your ears! Most of the time, banging or heavy vibrations are caused by a problem with the propeller, which could be bent, or otherwise damaged, causing the engine to “shake, rattle and roll.” Reduce your speed to lessen the rattling, until you can get the props looked at and properly repaired.

Noise and shaking can also be caused by loose or damaged motor mounts.

A damaged propeller is often the source of engine noise



Preventive Medicine Is Key

Like most of the systems on board your yacht preventive maintenance is key. The easiest way to ensure that any outboards you rely upon are ready when you need them, whether that is on your primary vessel or tender, is to make sure they are properly maintained.


Operating a motor yacht can be costly. You can reduce your expenses, and avoid costly repairs by keeping her well maintained. On Demand yachting from FYM can help. If you would like to learn more, or if you have any questions or comments about this blog post, do not hesitate to contact our Yacht Management specialists, or call us at (855) 318-6328.