Winter is once again around the corner and for a boat owner this means only one thing, it’s time to winterize the boat.
When I first winterized my boat I didn’t have any clue on what I should be doing, I read countless forums trying to find a proper guide that will tell me what I have to do step by step, but unfortunately I was unable to find anything. So I decided to make my own step by step guide that I’ve been following every year for more than 15 years.
Before I started using this guide I would spend at least a couple of days trying to make sure that I didn’t forget anything, but even so I would occasionally remember in the middle of the winter that I forgot to add fuel stabilizer, or to replace the gear oil. But now I follow this guide step by step and finish everything in just a couple of hours, and I never forgot to do anything. So let me show you my guide for winterizing a boat.
Note: I adapted this guide so that it’s usable on any kind of boat, so you should be able to use it for every type of boat: pontoon, jet boat, speed boat, sailboat, cabin boat, etc. So it’s possible to see some parts (mainly the one about the water system) that don’t apply to your boat, if that is the case you can skip that step and move to the next one.
Step by step guide winterizing a boat:
- Clean the boat
- Add fuel stabilizer
- Add antifreeze to the block
- Fogging the engine
- The water system
- The battery
- Cover the boat
- Wet vs Dry storage
So, those are the steps that you have to follow, now, let’s get into a little more detail about each step.
Table of Contents
Cleaning the Boat
The first thing that you should do is to clean the boat. While this might sound very trivial, it’s an essential step that you have to take.
Dirt, mud, and algae, can all deteriorate your boat over the winter. And in some really bad cases you can end up with mold on the boat. So make sure you give your boat a really good scrub if you don’t want to end up with a compromised hull.
Once this part is done, it’s time to move to the engine
Add Fuel Stabilizer
The first step in winterizing your engine is to top it up with fuel stabilizer. This will reduce the amount of air in the tank.
Air can hold a lot of moisture, and this moisture can end up as water at the bottom of your fuel tank, so making sure that there is little to now air in the tank is a priority. Most engines have a water separator, but even this separator has a limit, and when spring comes and you try to start your engine you will be met with an unpleasant surprise.
If you aren’t able to get the pump to top off your tank, you can simply add some fuel water absorber before you start the engine in the spring.
Add Antifreeze to the Block
This step will prevent any residual water from freezing and cracking the block when it will expand.
Some people will use a different way to remove the water from the block. They will remove the drain plug or open the petcocks in the block and blow compressed air through the raw water cooling system. The problem with this method is that it’s not completely safe. There is no guarantee that no water will remain in the system, and this water will end up cracking the system.
So instead of following that method, I would recommend you to simply flush the system with antifreeze, since it’s safer and a lot easier.
There are two types of antifreeze available, but only one is good for boats.
The first one is known as Ethylene Glycol, which is commonly used for cars. For cars this one will work great, but for most boats this type of antifreeze is bad. Boats with closed or freshwater cooling systems use a heat exchanger, and dissipate the heat into the water system, similar to what a car does. If your boat has a closed, or a freshwater cooling system, then you can use this type of antifreeze without any problem.
But most boats have a simpler raw cooling water system, this type of cooling system simply takes water from the lake, or ocean and circulates it through the engine block and then dumps it back into the lake, or ocean. For those types of engine you will have to use something known as a marine antifreeze.
A marine antifreeze is a nontoxic type of antifreeze. All the antifreeze in a raw cooling water system will end up dumped in the water or on the ground, and you don’t want to dump toxic materials in the water.
As for the concentration of the antifreeze, you generally want to get one that is as resistant as possible.
Fogging the Engine
Now it’s time to fog the engine. Fogging the engine means spraying it with anti corrosive oil.
This oil is usually sold under the name “fogging oil” but some brands might have a different name for it.
It usually comes in a spray-like can, and has a long pipe that can allow you to reach further, and tighter places.
The Water System
Smaller boats don’t usually have a water system so if your boat doesn’t have one you can simply skip this step.
Ust like in the case of the engine, if you don’t properly remove the water from the system you run the risk of ending with cracks in your system.
Luckily this process is very simple. You start by opening all the faucets and turning on the freshwater pump. Let them run until the water tank is empty.
After that pur 4 to 6 gallons of marine antifreeze in the tank.
Now slowly turn every faucet one, by one and close them when you see antifreeze coming out.
The Battery
Charge your battery completely and then disconnect it.
Leaving your battery connected will unnecessarily drain it, and you will have to buy a charge again in the spring, or worse, have to buy a new one.
An alternative is a trickle-charging unit which slowly charges the battery over a long period of time.
But the best solution is to simply store it in a warm room.
Cover the Boat
Now that the interior is taken care of it’s time to finally cover the boat.
The most important thing is to find a proper boat cover. A good boat cover will not only protect your boat from the cold and the snow, but it will also allow a good airflow.
A few good options are:
- polytarp cover with a frame,
- polyvinyl – for maximum water repellency),
- shrink wrap.
Shrink wrapping can be somewhat dangerous since it involves fire, so in my opinion it’s better to hire somebody to do this for you, instead of attempting it yourself.
Wet vs Dry Boat Storage
Now your boat is completely winterized, what is left to decide is where you should store it.
Both options, wet and dry, have their own advantages and disadvantages.
On the one hand, dry-stored boats can’t sink but, according to BoatUS, are more susceptible to freeze damage. On the other hand, wet stored boats, in a worst case scenario, can sink. And susceptible to osmotic blistering.
If you want to let your boat in the water, here are some tips:
- Inspect the dock lines. The declines are the only things that will keep your boat from drifting away, so make sure that they are in good condition, and if you have the chance to insect them during the winter as well, since waves and wind can put a constant strain on them.
- Install a de-icer. Installing a de-icer in your boat’s slip will help to prevent ice from forming, which can severely damage a boat.
- Use some dehumidifiers. Leaving your boat in water means that there will be a lot of humidity, so adding a couple dehumidifiers to your boart will reduce the humidity which can end up damaging the boat, especially if the airflow is not that great. Salt crystals can be used for this since they are quite cheap,they don’t leave any unpleasant smell, and are very good at absorbing humidity.
Final Thoughts
So that’s it. If you follow these simple steps your boat will be completely safe during the winter.
My suggestion is to follow steps 1 through 7 in that exact order, especially the ones involving the engine.
As I said in the beginning I’ve been following this exact guide for more than 15 years, and none of my boats had any problem during the winter. And if you swallow it as it’s described you shouldn’t have any problem either.
So in the end I will leave you with a quick recap.
- Clean the boat, this will prevent any damage done by algae, barnacles and mold
- Add fuel stabilizer, this will stop water getting into your engine
- Add antifreeze to the block, this will prevent water from freezing and cracking the block
- Fogging the engine, this will keep the exterior of the engine safe from rust and humidity
- The water system, empty it correctly so you don’t end up with cracks and leaks in the spring
- The battery, charge and remove it
- Cover the boat, get a good cover with a good airflow
- Wet vs Dry storage, if you decide to leave it in the water make sure you take the necessary precautions.