Is it necessary to fog a four-stroke outboard?

Boating enthusiasts often debate whether or not it’s necessary to fog a four-stroke outboard motor. Some argue that since these engines are designed to run on gasoline and oil, they don’t need the additional protection that fogging provides. Others contend that the corrosive effects of saltwater and storage can still harm four-strokes over time unless they’re properly winterized.

So what’s the truth??

First, let’s clarify what “fogging” actually means. Fogging involves spraying a fogging oil into the engine’s cylinders while it’s running, coating the internal components with a protective layer of oil. This can help inhibit corrosion and rust during extended periods of storage, particularly when the engine is exposed to saltwater environments.

While fogging was once considered a crucial step in winterizing all types of outboard motors, modern four-stroke engines have made it somewhat less essential. Most four-stroke engines are designed to run on gasoline and oil, which means they already have a protective layer of lubrication inside the engine. Additionally, modern four-stroke engines feature advanced corrosion protection technologies that can help prevent rust and other damage.

That being said, it’s still a good idea to fog your four-stroke outboard engine if you plan to store it for an extended period or if it will be exposed to saltwater environments. While four-stroke engines are generally more resistant to corrosion than their two-stroke counterparts, they can still suffer damage if left untreated. Fogging helps ensure that your engine will be protected against rust and other types of corrosion over time.

To fog your four-stroke outboard motor, start by warming up the engine so that its internal components are at operating temperature. Then, slowly pour a fogging oil into the engine’s air intake while it’s running. Allow the engine to run for a few minutes to ensure that the oil has spread throughout the engine, coating the internal structures.

While it may not be strictly necessary to fog a four-stroke outboard engine, it’s still a good practice to ensure that your engine remains protected against corrosion and damage over time. By taking the time to properly winterize and store your engine, you can help ensure that it will be ready to go when you’re ready to hit the water again.

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