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  1. How to Winterize a Boat
January 11, 2023

How to Winterize a Boat

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Nobody wants boating season to end, but when it does, it pays to be ready. To ensure that your boat is prepared for next season, all boaters should familiarize themselves with what their boat needs to be ready for winter. Here you’ll find a guide through the basic steps to winterize a boat, so you can go into the next season with confidence.

 

1. Winterize Boat Motor

 

Since your boat’s motor is one of its most critical components, protecting it from freezing damage will be your top priority. If the air temperature falls below freezing more than two days in a row, the resulting harm to your engine could be severe. Depending on what type of engine your boat has, the steps to prevent this may differ.

 

Winterizing an Outboard Motor

 

Avoiding freeze damage in an outboard motor, the first step is to change the oil in the lower unit, which will help remove residual water. Another place where excess liquid might remain is the cooling system, so next up is to flush this with fresh water. Keep the engine tilted down while doing this – since outboards are designed to drain completely in that position, nothing should remain behind. Next up is to change your engine oil and filter, again to avoid leftover water. And finally, if you’re planning to leave the engine for days at a time without running it periodically, it’s recommended that you coat the engine with fogging oil. This will form a thin film on metal components for long-term corrosion resistance.

 

Winterizing an Inboard Motor

 

With an inboard motor, the goal is similar as with an outboard – preventing freezing damage due to residual water. The process is slightly different due to the construction of an inboard engine. In order to effectively clean out the cooling system, you’ll want to run antifreeze through it until it starts coming out the exhaust, guaranteeing that the antifreeze has run all the way through the internal cooling passages. Be sure that the antifreeze you’re using is rated for engine use. Then, just like with an outboard, you’ll want to change the engine oil and filter to get rid of any remaining water, and fog the engine if it’s going to be sitting for a long period of time without running.

 

2. Prep Boat Gas Tank

 

Just like in both types of engines, water is the enemy that we want to avoid in your gas tank. Winter temperatures and condensation can wreak havoc with fuel and cause serious damage if your gas tank is not well prepared for the winter.

 

Fill Boat with Gas

 

Traditional wisdom is to fill your gas tank to 95 percent to limit the amount of air in the tank that can introduce moisture into the fuel through condensation and lead to harm from freezing temperatures. This may not always be necessary depending on your boat and the prescribed fuel – instead, some people allow the tank to get to almost empty and refill with fresh gas in the spring. In order to decide, do some research based on your fuel type and your boat. Always go with what your boat’s manufacturer recommends.

 

Add Fuel Stabilizer

 

No matter what you do with the fuel itself, adding a stabilizer to the remaining gas in the tank is an absolute must. Fuel stabilizers keep gas from going bad by bonding with the gasoline to prevent evaporation or formation of sticky resins. Spoiled gas would make for an unpleasant start to next season, and using stabilizer is a simple and easy step to avoid that.

 

3. Clean Boat for Storage

 

Your last step in prepping for winter will be to clean your boat. Doing this helps avoid easily-preventable damage, as leaving grime to sit on your boat’s surfaces all winter long can cause permanent damage to its finishes – inside and out. Additionally, you’ll want to make sure everything that can’t be tied down is removed from the boat, as many items that live on boats during the summer can easily be eroded by spending the long winter on board.

 

Clean Boat Interior

 

Start with the basic step of wiping down the interior of your boat, to ensure it is as clean as possible before going into storage. Let all of your surfaces dry thoroughly before storing to avoid mildew. You’ll also want to gather up all electronics, lines, life jackets, fire extinguishers, flares and anything else that you think could be detrimentally impacted by staying on the boat. Clean and inspect these items as well before next season – if they need replacing, make a note to do so before you launch.

 

Clean Boat Exterior

 

It may be somewhat difficult to clean your boat’s exterior yourself depending on your choice of storage situation, but the off-season is a still a great time to remove any build-up that has cropped up over the summer. This stuff can be hard to get at with your boat in the water, so the winter is a great opportunity to do it before its next use.

 

4. Cover Boat for Winter

 

In or out of the water, you need to choose a cover. The goal is to protect it from the harsh weather elements, be it ice and snow or just cooler temperatures and high winds. Your options will include plastic shrink wrap, tarps and fitted covers. Plastic is cheap, but they can be hard to fit over your boat and can be vulnerable to wind shifts, while canvas offers similar protection but with a longer lifespan and less susceptibility to movement overtime. Finally, many boats manufacturers offer pre-fitted covers that are designed to perfectly protect your boat. These can be more expensive, but they will fit the best and last the longest.

 

5. Store Boat for Winter

 

Now to decide where your boat will spend the winter. You can store it in water, out of water, on your property or at a boat storage facility. The ability to store in water will likely depend on location and dock access and some boat owners will not have that option. When it comes to the choice between your property or a facility, it’s worth considering cost and location, as well such factors such as whether your boat could be moved by professionals and security. The latter will likely be helpful if you do not have a trailer suited to your boat, or you’re not comfortable with the distance needed for transport.