Boat Winterization Checklist

Death, Taxes & Winterization

Unless you are one of the lucky boaters to live in an area that is warm year-round, boat winterization is a necessary evil.  It is a sad time of year for us boaters.  It means that cold weather is coming, or possibly already here, and your boating days have come to an end for the year.

Just like going to the dentist, taking the steps to have your boat winterized is something that nobody wants to deal with.  However, just as ignoring your dental health will lead to problems down the road, not taking the steps to have your boat winterized will be much more painful in the long run.

What needs to be done?

There is not a cookie cutter answer as to what needs to be done for boat winterization at the end of the season.  This will depend on many factors such as:  style of boat, type of engine, size of boat, equipment on your boat, and several other things.  We are going to keep the tips here basic and these checklist items should apply to most boats.

NOTE:  Please speak with a qualified marine service center for recommendations on what winterization steps need to be done to your specific boat.  We STRONGLY recommend paying a certified service center to handle all of your boat winterization needs (specifically engine components) rather than taking the DIY method.

1.  Winterize The Engine

The first and most obvious thing that needs to be done for boat winterization is to to winterize the engine.  This is the process of draining the engine of any water and then running anti-freeze through it.  This makes sure that any water that is in the engine does not freeze and crack the engine block or components.  The anti-freeze takes this process a step further and by running the motor until the “pink stuff” comes out the exhaust means all the water should be gone and replaced with anti-freeze.

You also have to take your fuel system into consideration during boat winterization.  Most service centers will add a fuel stabilizer to your fuel to prevent any problems come spring.  Be sure to ask if this is included in your boat winterization package.

2.  Winterize the Plumbing

This step will not apply to all boats, but if you have a fresh water system or ballast system on your boat, it most definitely applies to you.  Basically, think of any components in your boat that have water in them.  If you have a sink or transom shower hose, then there is a fresh water tank inside your boat.  You will need to drain this system of all the water.  It is also a good idea to replace the water with anti-freeze.  This is especially true for components with a motorized pump, such as a sink or shower.

3.  Maintain the Batteries

Maintaining the batteries in your boat is also an important step in boat winterization.  Boat batteries are expensive and take a long time to charge, so it is best to keep them healthy over the winter.  This might involve removing them for home maintenance, running a trickle charger to your boat wherever it is stored, or just asking your service center for their recommendation based on your situation.  You certainly don’t want your first boating weekend ruined by dead batteries and an engine that won’t crank at the launch ramp in the spring.

Here is an popular, inexpensive trickle charger on Amazon:

4.  Cleaning/Mildew Prevention

Step #4 on our boat winterization checklist is a must.  This can be a fairly simple and easy step, or a more in-depth process depending again on the type of boat you have and how you store it.  If your boat sits in the water all year, it will need to be hauled out of the water.  You will need to have the underside pressure-washed to remove the buildup.  This can apply to both fiberglass and aluminum bottoms, such as pontoons.  The only exception would boats with bottom paint, although that is a completely separate topic we will leave for another time.

Once the nasty underside is cleaned, you will want to wash the entire rest of the boat & trailer.  Be especially thorough if your boat spends any time in the saltwater.  If you have a fiberglass boat, once the outside is washed, take the time to put on a coat of wax.  This is a key step to ensure your boat stays looking good for many years down the road.

The inside of your boat will also need to be cleaned.  Once cleaning is done, use a vinyl conditioner on the seats.  Vinyl conditioner is the equivalent of wax for your boat’s interior.  It protects the vinyl from UV rays, staining, and keeps it soft and prevents it from drying out over time.

Don’t forget about cleaning under the seats and inside storage compartments.  You will want to get the interior and compartments completely dry if possible.  Any moisture trapped inside the boat over the winter can lead to mildew and odors.   You can use different products to help absorb any extra moisture, but don’t rely on them completely.  Mildew stains can completely ruin a boat’s interior, so you don’t want to take any chances here.  One product which can help is Starbrite No Damp Dehumidifier and Moisture Absorber.

5.  Cover Your Boat!

It goes without saying that after boat winterization your vessel needs to be protected from the elements.  Let’s take a look at some of your options.  If you store the boat indoors, this makes life much easier.  You don’t have to worry about snow, wind, rain or any of the elements.  In most cases, you should still keep your boat covered.  This can be snap covers or a full mooring cover.  Shrinkwrap is probably not necessary.  The only exception to this might be if you fear rodents could get into your boat.  Otherwise, we are just trying to keep the dust and light dirt out of the interior.

If you store the boat outdoors, you will need to be more proactive.  Snap-on covers would probably be the bare minimum you want to use.  They will keep the boat semi-clean, but dirt/water/snow/ice can still get between the cover and boat in most cases.  You will also need to have a support system in place (poles or straps). This prevents the cover from pooling with water or snow/ice.

Shrinkwrapping is the best option if you plan to keep the boat outside.  This seals the boat up very well and is the next best thing to keeping the boat indoors.  Shrinkwrap isn’t perfect though.  Animals can still tear it open.  Straps & tape can fail or break.  And even with a good support system, it’s best to still remove any snow or ice manually just to be safe.

Overview

Our boat winterization checklist is meant to be a basic list of recommendations that need to be done to most all boats in the wintertime.  This is not a comprehensive list.  One boat can be incredibly different than the next, so speak with a certified marine technician to be sure you are taking all the necessary steps to prepare your boat for winter.  Keep in mind, a boat prepared for winter quickly becomes a boat ready for summer when that wonderful time comes!