Boat on the Water

How to Winterize Your Boat

Not all boat owners live in perpetual warm weather. While living on the constant 100+ degree equator poses its own challenges for seacraft, those living where the seasons change have another concern — winter. 

As the final jacket-free days of fall begin to wane, you’ll need to turn your attention to your boat and prepare it for the chilly, freezing climate.


Why Should You Winterize Your Boat?

Most boats live perpetually outdoors, often in the water. Without the right precautions, boats can’t handle the constant freezing and thawing of water. 

Ice will build up on the surface of the boat, but more than that, any moisture in the electronics will crystalize, too. Rubber components can become brittle and crack, ice can expand inside joints and burst seals, and hulls can crack.

In short, winter weather will wreck an unprepared boat. Whether you store your boat in a heated, climate-controlled storage unit, on a trailer in your yard, or tied up at the marina, winterizing will ensure the boat is ready to use come spring. 


Collect Your Materials

To protect your boat for winter, you’ll need:

  1. Microfiber cloths (when you spill liquids, these cloths won’t scratch surfaces)
  2. Fresh engine oil
  3. Fuel stabilizer
  4. Antifreeze
  5. Oil filter
  6. Fogging oil
  7. A cover
  8. A dehumidifier or desiccants

If flexible or rubber parts of your boat have been damaged, such as hoses or gaskets, it’s best to replace them while the weather is still warm and your boat is not yet in storage.


Winterizing Your Boat

The best time to winterize your boat is before the weather drops below freezing. This is important not just for the health of your boat, but it’s for your benefit, too! Working on your boat while wearing a heavy coat, hat, and gloves can be restrictive. It’s best to do it while you can still get away with short sleeves.

1. Change the Engine Oil and Filter

Despite your best efforts, and regardless of how well-engineered your boat happens to be, contaminants and moisture will make their way into the engine. 

Before you change the oil, crank over your motor while the boat is still in the water. This will help the oil to thin out and drain more easily. Fill it up with fresh oil, swap out the filter for a new one, and test the engine to make sure it’s running well. 

2. Fog the Engine

Fogging the engine will protect it from internal corrosion. Older carbureted engines will need fogging fluid, while engines equipped with electronic fuel injection (EFI) will need a combination of gas and EFI fogging oil. If you can run the engine until warm once a week during winter, this will do the trick, too. 

After fogging, check your gear oil, if applicable. You’re looking for signs of water contamination. If you see any water, drain the oil and replace it. 

Also, if your engine has one, drain gas from the carburetor before storage. When in doubt, read the instructions on the bottle carefully and ensure you get the right oil for your engine! EFI fogging oil should only be used in EFI systems, and carburetor fogging fluid should only be used in carbureted systems.

3. Stabilize the Fuel

Even if you’re using zero-ethanol gasoline, you’ll still want to use a fuel stabilizer to ensure the gas survives in your tank for several months. Once you treat the fuel, run the engine for a few minutes to ensure all the gas in the system is stabilized.

4. Flush, Drain, Add Antifreeze

Use the pumps on the boat to eliminate water from the washdowns and live wells, but stop running the pumps once they are dry. Then, run antifreeze through the pumps. Next, flush the engine’s cooling system and add antifreeze. Test the engine to ensure it maintains a stable temperature. 

If your boat has a plumbing system for a head, sink, shower, etc., drain it, too. You want to make sure there is no water left in any of the systems that can freeze while your boat is in storage. Finally, remove the drain plugs.

5. Add Grease and Lubricant

Apply grease to the grease fittings, as well as a marine lubricant. This will fight rust and corrosion.

6. Clean Your Boat and Wax It

Cleaning the boat will ensure that no contaminants, dirt, or debris stay on your boat for months on end. Waxing it will apply a protective coating that will last until spring.

7. Cover and Dehumidify

Ideally, your boat will be in dry storage, but that’s not always possible. Use a quality cover to protect the boat from precipitation if outside and leaks if it’s inside. Also, you can use a dehumidifier and desiccants to ensure it doesn’t foster mold and mildew growth.


Enjoy Your Boat in Spring!

If you’ve properly winterized your boat, you’ll be ready when the cold weather goes away. Make sure to check on your boat throughout winter to ensure it’s staying in ship-shape.


When it comes to keeping your boat clean, look to Captains Preferred Products boat cleaning supplies. Find everything you need to keep your vessel squeaky clean all season — always at the best prices.

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