Performing Yamaha 2-Stroke oil maintenance is the first step for completing your 100-hour service. Of course, completing needed maintenance in a timely manner on your Yamaha outboard is the key to its overall longevity and reliability. So let’s get started.

100-Hour Service – Yamaha 2-Stroke Oil Maintenance

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If your two-stroke Yamaha outboard has oil injection with a remote oil tank inside the boat, you will begin your service by accessing this tank. These remote tanks are not always situated in the easiest-to-reach places, so you may have to consider removing a livewell tub, cooler, or access panel to get to the tank. Loosen the tank from its bracket and locate the oil supply hose that comes from the pump on the tank and heads toward the engine. You should notice a small, white, inline filter that strains the two-stroke oil in route to the engine. This small filter is often overlooked, but without a steady supply of Yamalube two-stroke oil, your engine will quickly go into reduction mode, or worse. Cut the small zip ties that secure the oil line to the strainer and replace the strainer quickly before you drain oil all over the bilge. This process is a little messy, so a few petroleum sorbent pads can help avoid a mess. Having some good quality nitrile gloves on board the boat or around for your service is also a great idea.

With the tank loosened from its bracket, it is a great time to use a small service flashlight to illuminate the bottom corners of the tank. The clear plastic will allow you to spot any debris or water deposits accumulated inside the tank. If found, you will need to remove the tank, drain, and clean. Debris is most often introduced from fill caps being left open, damaged fill cap o-rings, or dirty containers used to purchase bulk oil.

When complete, reinstall the tank into the bracket and remove the cowling from your engine. Use the manual transfer switch on the side of the engine to verify oil is flowing through your new filter and the system is primed. Your Yamaha 2-stroke oil maintenance is now complete. You are ready to begin your engine service.

How to Perform Yamaha 100-Hour Service eBooks

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