Yamaha EX, EX Sport, EX Deluxe Waverunner 2020 Owner's Manual
![Yamaha EX, EX Sport, EX Deluxe Waverunner 2020 manual cover](/images/9c4ac3202ca53afec8cf2c0e/thumbs/thumb175x175.webp)
The recommended maintenance schedule for the Yamaha EX series includes an initial service at 10 hours of use, followed by regular maintenance every 50 hours or annually, whichever comes first. This includes checking and changing the engine oil, inspecting the cooling system, and checking the spark plugs.
To flush the engine, first ensure the Waverunner is securely on a trailer or stand. Attach a garden hose to the flushing port. Start the engine and then turn on the water. Let it run for about 10 minutes, then turn off the water before stopping the engine. This helps prevent salt buildup and corrosion.
These models are designed to run on regular unleaded gasoline with a minimum octane rating of 87. It's important to avoid ethanol blends over 10% to prevent engine issues.
If your Waverunner won't start, check the battery connections and charge level. Inspect the fuel level and ensure the fuel is fresh. Examine the spark plugs for wear or fouling. If these steps don't resolve the issue, consult a Yamaha technician.
To winterize your Waverunner, begin by cleaning it thoroughly and draining any water from the hull. Add fuel stabilizer to a full fuel tank, and run the engine briefly to circulate the stabilizer. Remove the battery and store it in a cool, dry place. Cover the Waverunner with a breathable cover.
The Yamaha EX Deluxe features electronic trim control. Adjust the trim up for higher speeds and smoother water conditions to lift the bow and reduce drag. Trim down in rough conditions to lower the bow for better control.
Before each ride, check the oil level, inspect the hull for damage, ensure the throttle and steering operate smoothly, and confirm the lanyard stop switch functions properly. Additionally, verify that all safety equipment is on board.
To improve fuel efficiency, maintain a steady throttle and avoid sudden accelerations. Ensure the Waverunner is not overloaded and remove any unnecessary weight. Regular maintenance, such as keeping the engine well-tuned and the hull clean, also contributes to better fuel economy.
For the first 10 hours, avoid operating at full throttle. Vary the engine speed and avoid prolonged idling. After the initial break-in period, schedule a service to check the engine and change the oil. Following these steps ensures optimal engine performance and longevity.
It is not recommended to tow a Waverunner behind a boat as it can cause water ingestion into the engine. If towing is necessary, use a tow valve to prevent water from entering the exhaust system and keep speeds below 5 mph.