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While your Yamaha Watercraft dealer can help you with, or even do, most of your general and preventative maintenance, corrosion mitigation is something you can only do yourself—and time is of the essence

Regardless of where you boat, corrosion attacks both the inside and the outside of your WaveRunner—every day, all the time. Some forms you can see, some you can’t, and it can take only a short time for the damage to begin. Even those boating in freshwater have corrosion-mitigation duties to attend to. Why, even rainwater can have corrosive effects that can be damaging to your WaveRunner. So it’s vital to be diligent in your anti-corrosion defense. Your dealer can help provide the right products to help prevent some forms of corrosion, but their regular and diligent use is strictly up to you.

The following are answers to common questions about how to mitigate the presence and damage of corrosion.

Where do I need to concentrate my fight against corrosion?

Corrosion can happen pretty much anywhere on or in your WaveRunner: inside, in your fuel system or in the internal cooling water passages, and on the outside, in various electrical connections and exposed metal components. But don’t worry, you have a lot of allies on your side, and we’re here to help by teaching you where to look and what to look for.

What’s so important about flushing my WaveRunner engine? I boat exclusively in freshwater, do I still need to?

Your Yamaha WaveRunner is raw-water cooled, meaning it uses the water it’s operating on as cooling water. All water, fresh or salt, contains contaminants that will eventually build up in the cooling passages over time. Additionally, saltwater is naturally corrosive and any remaining in those cooling water passages after use are left there to do its worst, unabated. Saltwater can also experience crystallization when exposed to heat above 170 degrees, which causes deposits to form and potentially restrict cooling water passages. For these reasons, it’s a must that you flush your engine thoroughly with fresh, clean water after every use.

What causes it and what can I do about it?

Dry corrosion occurs in areas not in direct contact with water—exhaust systems, for example. The outside of most exhaust system components is cooled by raw water to prevent overheating. When today’s ethanol-enhanced fuel is burned, it creates by-products known as sulfate salts. These salts are highly corrosive, especially when exposed to very hot temperatures. If the WaveRunner’s  cooling water passages are not kept clean by regular flushing (the exhaust area in this example), hot spots can form on the interior of the exhaust components, concentrating the sulfate salts’ corrosive effects. In effect, it’s corrosion from the inside out. That’s why flushing your engine with fresh, clean water for 15 minutes after each trip is a vital part of preventing even dry corrosion. It helps the cooling system run at maximum efficiency by keeping the cooling water passages clean and clear, which helps minimize the heat inside the engine, making it less susceptible to dry corrosion.

How can I fight corrosion on the outside of my WaveRunner?

It’s a good practice to set up a regular schedule and stick to it. There are quick and simple things you

should do after every use if you boat in saltwater, and periodically if freshwater is your game. These include visual inspections you should do every time. If you’re unsure about what to do and when, your authorized Yamaha Watercraft dealer can help.

Rinse it. Don’t spare the hose when returning from a trip, particularly in saltwater. Rinse the entire outside of the engine with clean water. Give the outside of the WaveRunner a once over with some mild soap like Yamalube Wash and Wax Concentrate and a soft cloth. (Do not use a liquid dish soap, as it can strip off important protectants. Go ahead and wash the whole boat and trailer. Wiping it down with a good quality chamois afterward helps keep it all looking sharp. 

Note: If salt build-up has become a problem, or your WaveRunner’s engine has somehow been directly in contact with saltwater, it’s okay to gently rinse portions of the engine with clean, fresh water to remove salt and other nastiness. Just use a hose on low pressure—not a spray attachment—and don’t rinse around the air intake area. Rinse out the inside of the cowling, too. Make absolutely sure both engine and the seat are completely air dry before reinstalling the seat. 

  • Spray it. Liberally spray the entire dry powerhead with a protectant like Yamashield.™ It’s a lubricant, a water displacement agent and a corrosion preventative all rolled into one. A high-quality silicone spray works well here, too. Spray all external powerhead surfaces and the electrical connections to help keep them corrosion-free, and the rubber cowling sealing gaskets to help keep them supple and effective at sealing out harmful water.

Check it. Do a quick visual inspection of your WaveRunner every time you use them. Look for anything out of the ordinary and investigate if need be.

Keep a special eye on:

Electrical systems: Check the battery terminals. If corrosion appears on either, Yamalube® Battery

Terminal Cleaner & Protector will do the trick. Spray it on to clean the affected areas (heavily corroded connections will first need to be disconnected and thoroughly cleaned). When it dries, it leaves a protective waxy film that will help keep corrosion from re-forming.

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