Common Yamaha Outboard Problems

Yamaha is world renown for making some of the most powerful, durable and reliable outboard engines on the marine market, but they’re not without their problems. 

Regardless of make and model, all outboard motors eventually encounter problems due to maintenance issues and/or normal wear-and-tear. However, two incredibly popular Yamaha outboard models in particular are notorious for experiencing problems: the Yamaha F225 and F115 models.

What Year Yamaha Outboards Had the Most Problems?

When it comes to the F-Series of four-stroke Yamaha outboards, the first generation models manufactured between 2000-2005 are the ones that stand out. The F225 models in particular experienced some controversy due to severe and unusually fast dry exhaust corrosion problems after only 500-700 hours of use, which in most cases would happen just after the three-year warranty period had expired. 

Yamaha Outboard Exhaust Corrosion

Yamaha sold a repair kit for the exhaust corrosion problem, but did nothing else about it if the warranty had already expired. So many first-generation Yamaha F225 owners got stuck with thousands of dollars’ worth of repair bills to fix the problem, which included severe corrosion and pitting of exhaust passages that allowed hot gases to ruin the engine. This led to problems that included loss of horsepower, smoking and premature engine failure.

Exhaust corrosion was a major problem on our 2004 Yamaha F225, which led to the need for an exhaust system rebuild. Watch our Yamaha outboard exhaust rebuild in the video below. 

Other Common Yamaha Outboard Problems

While the severe and premature exhaust corrosion mainly affected first generation Yamaha F-Series models, other common issues are known to happen with Yamaha outboards in general. The following issues are notable as common problems with the popular Yamaha F115 four-stroke outboards, but they can happen to just about any outboard make and model over time. 

Failing Head Gaskets

One common problem associated with Yamaha F115 outboards is faulty head gaskets. Whether it’s the Yamaha F115 or any other outboard make or model, the fact is head gaskets wear out and fail over time.

When head gasket failure happens, water and other contaminants will eventually pass through the engine. A faulty head gasket can also cause engine overheating, severe damage and eventually total engine failure. 

Our Yamaha F225 outboard needed an entire powerhead rebuild, including a new cylinder head installation with new head gaskets. Watch the video below to see our Yamaha outboard top end rebuild.

Fuel System Problems

Other problems Yamaha 115 outboards are known for have to do with the fuel system, including bad fuel pumps, and clogged fuel injectors, fuel filters and VST (vapor separator tank) filters.

Once again, these problems aren’t exclusive to Yamaha F115 outboards, and are all outboard fuel system parts that eventually need replacing. A bad fuel pump and clogged filters can bog down an engine and lead to all sorts of starting and idling problems.

For the fuel pump, preventing problems includes keeping the gas tank full, using low-ethanol fuel, and adding fuel stabilizer when refueling. As for clogged fuel filters, proper fuel system maintenance helps keep them clean. Flushing the engine regularly is recommended, as well as inspecting and replacing the filters often. If the filters are clogged, they’re cheap to replace, so don’t ignore regular inspections. Cleaning the fuel injectors — which can get clogged due to carbon buildup and cause engine misfires and vibrations — is also recommended.

Our Yamaha F225 outboard experienced all kinds of fuel system problems, which called for an entire fuel system rebuild. Watch the video below to see how to rebuild a Yamaha outboard fuel system, including cleaning the fuel injectors.

Tips for Preventing Yamaha Outboard Failure

Preventing problems with Yamaha outboard motors (or any outboards for that matter) mostly comes down to routine maintenance. Here are some things you can do to prevent Yamaha outboard failure.

Fuel System Problems

• Stick to premium low-ethanol fuel for Yamaha outboards. Ethanol attracts water, which can dilute fuel and gunk up fuel system components. 
• Inspect fuel lines regularly for leaks and cracks, and replace them as needed.  
• Replace fuel filters at least twice during the boating season, and inspect them regularly for clogs.
• Test the fuel pump if you think it’s not working correctly. If the fuel pump has failed, replace it and any hoses that connect to it.

Cooling System Problems

• Never dry start your Yamaha outboard, as the motor relies on a continually flowing water supply to cool the engine. The water pump impeller is also lubricated by water, so a dry impeller can lead to warping, cracking and fins breaking off into the engine.
• Inspect and replace the impeller regularly, which is an easy fix. Yamaha water pump repair kits are available that include a new impeller. Changing out the impeller alone is an option, but replacing the entire water pump is recommended since you’re going through the trouble of removing the lower unit anyway.

Watch the video below to see how to replace the water pump on a Yamaha outboard.

Electrical/Ignition System Problems

• Inspect the main fuse to make sure it’s not burnt out. Replace any blown out fuses with new ones of the same amperage.
• Test the battery by disconnecting the negative cable first and then the positive cable before removing the battery. Replace the battery if the test shows failure to hold a charge or the battery is dead. If the battery is good, use a wire brush to scrape off any corrosion from the battery terminals, then charge the battery and reinstall it.
• Test the spark plugs by removing each one with a spark plug wrench. Check for cracks, fouling or corrosion, and replace the spark plugs and their wires with the type recommended by Yamaha in the owner’s manual.  

Watch the video below to see how to troubleshoot problems with an outboard engine that has spark but won’t start.

Engine Vibration

• Inspect the propeller and its parts for any damage, and make sure none of the prop hardware is loose. If you find any nicks, bends, pitting or broken fins on your Yamaha outboard’s propeller, repair or replace it immediately.
• Check to see if there’s any fishing line, seaweed or other debris tangled up in the propeller and the prop shaft. Check the propeller shaft as well for damage. Make sure the engine is mounted correctly, and that all bolts are tightened. Finally, restart the outboard to see if the vibration is gone.

While inspecting the propeller and prop shaft for possible engine vibration causes, check the prop shaft seals too. Watch the video below to see how to the replace prop shaft seals on a Yamaha outboard.

The majority of the videos featured above are part of a larger project to rebuild an entire F225 engine that experienced many of the common Yamaha outboard problems listed above. Watch the videos below to learn more about why this 2004 Yamaha F225TXRC outboard needed a rebuild, and to see the actual F225 powerhead rebuild in its entirety.