How to Winterize a Boat: The Simple Guide

How to Winterize a Boat: The Simple Guide

Around the country, winter weather can be brutal. If you own a boat, it is essential that you take steps to winterize it before these cold temperatures move in.

If you need to know how to winterize a boat, you are in the right place. Keep reading to learn more about the steps to take to ensure your boat is winter-ready.


Replace the Oil in the Boat’s Engine

Acids and moisture in older oil can cause serious problems. When you put your boat in storage, if you have not replaced the engine oil, these elements can cause pitting to the bearings and other parts of the engine.

The first step in this process is to drain the existing oil. However, you need to warm up the engine to do this, all while your boat is in the water.

When you use this process, you can feel confident as much of the dirty oil as possible will come out, and the impurities that are present will flush out with ease. When it comes to boat and RV storage during the winter, this is a step you cannot forget or ignore.

Once the oil is drained, you need to replace it with a winter-ready, high-quality brand. Be sure to change the oil filters, too.

If you have a four-stroke, outboard motor, make sure you change the filter and the oil before you put the boat up for the winter.

Drain and Flush the Cooling Water

Water freezes – this is a well-known fact. This means that you need to make sure there is no water left in your boat’s engine. If it is, you need to drain it out so that the water does not freeze, expand, and cause serious damage.

The steps you take for this process depends on the type of engine you have.

Sterndrive and Inboard Engines

For these types of engines, you will flush your engine using clean water. You can do this with a water muff or something similar.

You should never run a water engine if no water is present. Once you have the tool needed, you must flush the engine until it reaches the typical operating temperature.

The next step is to remove the drain plugs. You can find these in the manifold and engine block, in most cases. It may also be necessary to remove the hose connected to your boat’s water pump. This will allow any remaining water to drain.

Outboard Engines

If you have an outboard engine, draining and flushing are also needed. However, the process is a bit different.

The first step is to ensure all the drain holes have been opened. Start your boat’s engine and then clean the cooling system. This is done by continually flushing it using freshwater.

Continue the flushing process for several minutes.

Stabilize the Fuel

Did you know that the fuel in your boat can completely deteriorate in just 60 days? In some cases, issues may be seen after just 15 days.

When the fuel in your boat’s gas tank deteriorates, it can cause varnish and gum to begin building up in the engine. This can result in reduced engine life, improper performance, and hard starting.

One of the fastest and most effective ways to prevent this problem is using a high-quality stabilizer. Make sure to choose one made for boats and marine vessels.

Once you have purchased the right stabilizer, you should fill the tank with new fuel. This will prevent the possibility of water condensation, which can cause corrosion.

Turn the engine on for several minutes to get your treated gas to cycle through the entire system. You can do this while your boat is still on the water or by using a fitting that runs the engine with a garden hose.

It would help if you understood that draining the gas will not prevent the formation of varnish in all engines. This is because some fuel will always be left behind. The gaskets may also dry out and result in leaks when you start the boat up in the spring.

Protect the Engine Parts and Components

When your boat is put in storage, the engine oil will begin to drain away. This can cause the internal engine components to be exposed to the harsh winter elements.

Over time, this may cause metal-to-metal contact, corrosion, and more.

The good news is that you can prevent these problems. For example, with a fogging oil spray, you can feel confident these issues will not occur.

These provide are formulated to get deep into your boat’s internal engine. It will coat the parts with a protective layer that will prevent corrosion during the winter months.

Replace the Gear Oil

When it comes to a boat’s engine, there is a lot to do to get it ready for winter weather. Along with the steps above, you must also drain the lower unit of all gear oil.

Once drained, you need to replace it with new oil.

When you are changing this oil, make sure you look for any signs of moisture. Some symptoms of moisture include:

  • Water that comes out first
  • Lumpy oil
  • Milky oil

All these are signs that your boat is dealing with moisture contamination. You should purchase and install new seals before the upcoming boating season.

Take Time to Lubricate and Grease

You need to locate the grease fittings in your boat’s engine. Most of these are going to be found in the area of the steering mechanism.

Once they are located, use a quality marine-grade lubricate to provide protection. The right lubricant will protect against oxidation, corrosion, and rust.

Be sure to look in the boat’s owner’s manual to know everywhere this product should be applied.

Remove Your Valuable Items

While most boat storage locations have very little traffic during the winter months, this is not necessarily good. When there aren’t many people around, it means that a break-in may be more likely.

Be sure that you take out anything of value on your boat. If possible, purchase boat insurance.

Inspect the Hull

While making sure the engine and internal components are protected is essential, those are not the only important steps to protecting your boat.

Most boats are built using fiberglass. While this material is designed to stand up to saltwater and hot temperatures, you may think a little snow is no big deal.

Unfortunately, if ice accumulates in window tracks or open hatches, it can cause a lot of damage.

If you plan to store your boat outside, you must have a quality cover.

It is also a good idea to inspect the hull. Check to see if there are any stress cracks, usually seen around the Gelcoat blisters and bow eye.

If stress cracks are present, it means there is structural damage. At this point, you should bring in a professional for a full evaluation of the issue.

Any barnacles or other items on the base of your boat need to be scraped off. You can also pressure wash your boat before putting it in storage to prevent staining and other long-term issues.

Protecting the Interior

The winter air can be both dry and humid. Both of these conditions can wreak havoc on vinyl interiors.

Find and use the right vinyl cleaners and protectants to prevent these issues. They will keep the material from getting too dry or cracking.

If there is too much moisture present, it can cause mold and mildew to form. Don’t let this happen by venting the boat properly.

When there is proper airflow through your boat, it will dry out any moisture and prevent mold and mildew development.

Keep in mind, along with causing mold and mildew; moisture can damage your expensive electrical system and electronics, too. It is up to you to ensure everything is protected from damage.

Now You Know How to Winterize a Boat

The answer to “how to winterize a boat” is not simple or short. You must use all the tips and information above to ensure your boat is fully protected from frigid temperatures.

It is also necessary to find the right storage location for your boat. You can find several commercial properties, or you can store your boat at home. Regardless of what you choose, protecting all the inner workings of your boat will help ensure it is ready to hit the water when warmer weather returns.

Are you ready to find more interesting and engaging articles? Do you need practical advice? If so, be sure to check out some of our other blogs.

Leave a Reply