Troubleshooting Your Yamaha 4-Stroke Motor

3 Yamaha XTO outboard motors on Contender fishing boat

Troubleshooting Your Yamaha 4-Stroke Motor

A Guide From Eric's Outboard Marine Service in Miami, Florida

It’s no secret that Yamaha offers one of the most impressive 4-stroke outboard motor lineups on the market. If you’re the proud owner of one of these engines, you know just how powerful and reliable they can be. No matter what model you have, there will eventually come a time when you may need to troubleshoot some common issues. If you’re not quite sure where to begin, then you’ve come to the right place. Eric’s Outboard Marine has created this guide with some tips for troubleshooting your Yamaha 4-stroke motor.

If you have questions or need assistance, don’t hesitate to contact our dealership in Miami, FL. We also serve those in Broward County and Miami-Dade County.


There are a few steps you can take to troubleshoot starter issues. If it’s not engaging or turning over, you may have a faulty electrical system. For electric-starting models, you’ll want to check the main fuse to confirm it’s not blown. Start by unscrewing and removing the electrical cover. Next, use a pair of pliers to remove the fuse holder. If you find that the connection at the center of the fuse is broken, then you’re dealing with a blown fuse. You’ll need to replace it with one of the same amperage, which you can find listed in your Yamaha outboard owner’s manual.

If you don’t have a blown fuse, your next step is to check the battery. Be sure to safely disconnect the negative cable followed by the positive cable before you remove the battery from its housing. Carefully scrape away any corrosion on the battery terminals with a wire-bristle brush. Take the time to clean off any other debris or buildup with a solution of one cup of water and one tablespoon of baking soda. Don’t forget to completely dry the terminals with a clean towel when you’re finished.

If the battery is damaged, you should replace it. If not, you can proceed to charge it. When it’s completely charged, reinstall the battery and cables. Remember to connect the positive first and the negative second. Once that’s done, you can try the Yamaha outboard’s starter again. If it’s still not starting, you’ll want to consult a professional to inspect the electrical system. Your friends at Eric’s Outboard Marine would be happy to help. You can count on our Yamaha Certified Master Technicians to get to the bottom of it.


If you’re experiencing issues with the engine starting or running, there are some troubleshooting steps you can try. First, check the fuel system to ensure there is enough fuel in the tank. If the levels are low, refuel it with the appropriate gasoline for your model. Next, check the fuel lines that connect the Yamaha outboard motor to the fuel tank. If you find any breaks or leaks, you should stop using the engine. You’ll want a professional to handle this as soon as possible.

You’ll also want to check the engine oil levels. Make sure the motor is upright and level before removing the oil filler cap and dipstick from the oil tank. Wipe the dipstick off with a clean cloth, reinsert it, then remove it and check the oil mark. If the level is below the “L” mark, you should refill the tank. Alternatively, if you find the level is above the “H” mark, you should remove excess oil with a syringe.

Your last step involves the spark plugs. Remove them with a spark plug wrench so you can inspect them. If they’re burned or cracked, you should replace them with the type of spark plug specified in your owner’s manual. You should also measure the spark plug gap with a wire thickness gauge to confirm the gap falls within the range listed for your model. Adjust it with a spark plug gap tool if necessary. When you’re done, reinstall each spark plug and place the caps back on.


Another common issue that you may need to troubleshoot is vibration. If you’re experiencing excessive vibration, you can start by checking the condition of the propeller. If you find any damage, you’ll need to remove it and bring it in for repair or possible replacement. If there’s no damage, the next step is to remove any seaweed or other debris that might have become entangled in it. While you’re at it, check the propeller shaft for damage. Once again, if you find damage, you’ll need to take it in for repairs. Lastly, tighten the motor mounting bolt and the steering pivot with a wrench. Restart the engine to see if the vibration has stopped. If not, it’s time to bring it in for an inspection.

We hope these tips for troubleshooting your Yamaha 4-Stroke Motor have come in handy. If you’re still experiencing issues, you can always reach out to the team of professionals at Eric’s Outboard Marine. Our highly trained and qualified staff looks forward to assisting you with all of your outboard service needs. You’ll find us located in Miami, FL. We’re proud to serve all of southeast Florida.

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Please feel free to contact us or stop in today for all your outboard motor needs! Call us at (305) 251-4067 or contact us below.