Fogging A Boat Engine: A Step-By-Step Guide

Fogging a boat engine is a crucial step in winterizing your boat. It involves spraying fogging oil into the engine to prevent rust and corrosion. This process is necessary to protect the engine from freeze-related damage and to ensure its smooth operation when you take your boat out of storage. Fogging oil acts as a long-term lubricant and corrosion-resistant agent, forming a thin film on metal components that remains intact over time. It is recommended to fog your boat engine before storing it for the winter to maintain its performance and extend its lifespan.

Why you should fog your boat engine

Fogging your boat engine is an important step in the winterization process, which can extend the life of your engine and prevent costly repairs from freeze damage. Here are some reasons why you should fog your boat engine:

• Prevent Corrosion: Fogging oil acts as a long-term lubricant and corrosion inhibitor. It forms a thin protective film on metal components, preventing rust and pitting caused by ambient moisture. This is especially important for boats stored in cold, humid environments or those with ethanol-enhanced gas, as ethanol can attract moisture and cause corrosion.
• Lubrication during Storage: During storage, gravity causes oils and lubricants to drain away from critical engine components like cylinder walls and piston rings. Fogging oil provides a long-lasting coating that remains intact over time, ensuring these parts remain lubricated and protected.
• Engine Health: Fogging can help maintain engine health by preventing cylinder scuffing and stuck piston rings. It also helps prevent varnish and gum buildup in fuel lines, carburetors, and fuel injectors, ensuring a smooth start in the spring.
• Easy to Administer: Fogging oil is easy to use and can be administered by any DIY enthusiast or experienced mechanic. Simply spray the fogging oil into the air intake until the engine stalls, or remove spark plugs and spray directly into the cylinders.
• Cost-Effective: Fogging your boat engine is a cost-effective way to protect your investment. It is much cheaper to fog your engine than to repair or replace engine parts damaged by corrosion and lack of lubrication.

By taking the time to fog your boat engine before storage, you can rest assured that your boat will be in tip-top shape and ready for the next boating season.

How to fog a boat engine

Fogging a boat engine is an important part of winterizing your boat to prevent damage from freezing temperatures. Here is a step-by-step guide on how to fog a boat engine:

Step 1: Prepare the Engine

Before starting the fogging process, it is important to prepare your boat engine for winterizing. Fill the fuel tank with gas and add a fuel stabilizer to prevent water condensation and gunk buildup. Warm up the engine by running it while the boat is in the water or using an adaptor and motor muffs with a hose.

Step 2: Add Antifreeze

The first step in the winterization process is to add antifreeze to your engine to prevent water condensation and freezing. Choose a non-toxic propylene glycol antifreeze to avoid releasing toxins into the water. Follow the boat manufacturer's specifications for draining the engine block and adding antifreeze.

Step 3: Spray Fogging Oil

The next step is to spray fogging oil into the engine while it is still warm. Fogging oil is an aerosol petroleum treatment that provides long-term lubrication and corrosion resistance. You can spray the fogging oil into the carburetor or directly into the engine's combustion chamber by removing the spark plugs. Be generous with the amount of fogging oil, as it will form a protective film on the metal components.

Step 4: Final Steps

After fogging the engine, there are a few final steps to complete the winterization process. Change the engine oil and replace the oil filter to remove any contaminants and acids that can harm the engine during storage. Check the exhaust system for corrosion and inspect hoses and hose clamps for any damage. Finally, seal off any cracks or openings to prevent damp air from entering the engine.

When to fog a boat engine

Fogging a boat engine is part of the process of winterizing your boat. Winterizing your boat is crucial to prevent gunk from building up, keep condensation out of the fuel tank, and to keep your engine healthy overall.

Fogging your engine is particularly important if your boat is going to be stored in a location with freezing temperatures. This is because fogging oil protects your engine's internal components during storage by coating the entire intake, cylinders, valves, and exhaust in a slightly tacky oil that will not be washed away by condensation.

If you do not plan to store your boat over winter, fogging your engine is not necessary. However, if your boat will be stored in a location with freezing temperatures, it is important to take the necessary steps to protect your engine, even if it will only be stored for a short period.

In addition to fogging the engine, there are several other steps involved in winterizing your boat, including:

• Filling the tank with gas to prevent condensation
• Adding a fuel stabilizer to prevent buildup in fuel lines, injectors, and carburetors
• Applying antifreeze to the engine to prevent water condensation from freezing and causing cracks
• Changing the engine oil and filter to remove contaminants and acids that can harm the engine during storage
• Sealing all openings to the engine to prevent damp air from getting inside

By following these steps and paying close attention to the specific needs of your boat and engine, you can help ensure that your boat will be in tip-top shape when the boating season begins again in the spring.

What fogging oil to use

Fogging oil is an aerosol petroleum treatment that provides long-term lubrication and corrosion resistance for engines in storage. It forms a thin film on metal components, protecting them from the effects of fluctuating ambient temperature and humidity, which can cause condensation and corrosion in as little as 30 days.

There are several fogging oil products available, including STA-BIL, which is recommended by Gold Eagle, and Star brite Fogging Oil, which is used by West Marine. Yamaha Outboards also has its own fogging oil product.

When using STA-BIL fogging oil, the manufacturer recommends the following process:

• Start the engine and remove the air filter.
• While the engine is running, spray the fogging oil into the air intake of each cylinder.
• After 10 seconds, shut off the engine.
• Remove the spark plugs carefully.
• Spray the fogging oil into each cylinder via the included extension tube for three seconds.
• Replace the spark plugs.

Fogging oil can be used on any gasoline 2-stroke or 4-stroke engine, including inboard and outboard boat motors. It is important to note that, if using an EFI-type motor, you should only use fogging oil formulated for EFI motors, as fogging oil for carbureted motors can clog the fuel injectors.

How much fogging oil to use

Fogging oil is an aerosol petroleum treatment that provides long-term lubrication and corrosion resistance for engines. It is particularly useful for boat engines that are being stored over the winter, as it prevents cylinder scuffing and stuck piston rings.

To fog a boat engine, you will need to spray fogging oil into the engine. The amount of fogging oil you will need depends on the size of your engine and whether it is an inboard or sterndrive engine. For inboard and sterndrive engines, you will need to spray the fogging oil into the carburetor until the engine stalls or begins to emit white smoke. This may take a generous amount of fogging oil. Alternatively, you can remove the spark plugs and spray the fogging oil directly into the engine's combustion chamber.

If you have an outboard motor, you will need to spray the fogging oil into the air intake just before the engine runs out of fuel. For two- and four-stroke carbureted motors, you will need to combine this step with flushing the motor with antifreeze. First, run the motor for five to ten minutes, then shut off the motor and hook up the winterizing kit to the flushing muffs. Fill the winterizing kit's tank with antifreeze, then remove the cowling to access the air intakes on the front of the engine. Open the valve to the winterizing kit, restart the motor, and watch the antifreeze level drop. When you begin to see antifreeze discharging from the exhaust, start spraying fogging oil into the carburetor until the engine dies.

For outboards with electronic fuel ignition (EFI), the procedure is a little different. Instead of spraying fogging oil into the cylinders through the carburetor, you will need to run the fogging oil directly through the fuel system. This is usually done by running a fuel line from the motor to a small container of stabilized gasoline mixed with fogging oil. Consult your owner's manual for the correct type and amount of fogging oil to use, as using the wrong type of fogging oil can damage your engine. Run the motor until you see white smoke exiting from the exhaust, then shut off the motor before the winterizing kit runs dry.

Frequently asked questions