Winter is coming, and if you live in a region where temperatures drop, it’s time to winterize your boat. Even if you're lucky enough to boat year-round in places like South Florida, where winter is more of a rumor than a reality, proper storage is essential to keep your boat in prime condition. If you keep your boat in a hard freeze zone like Chicago or New Jersey, the need to winterize your boat is a given. And for those in regions with unpredictable cold snaps, such as the Carolinas, Chesapeake Bay, or even Northern California, winterizing is the best way to avoid costly damage and ensure a hassle-free return to the water in the spring.
This article is a general introduction to the products used and the practices employed in the winterization process.
- The Risks of Not Winterizing
- Antifreeze: Your Ally Against Jack Frost
- Virgin Antifreeze is Best
- Selecting Antifreeze Based on Value
- Typical Winterizing Tasks
- Winterizing FAQs
- Conclusion
- We’re Here to Help!
- Related Articles
The Risks of Not Winterizing
Left unprotected, cold temperatures can cause water in the engine, the freshwater tank, sanitation or other systems to freeze, which can cause expensive damage to system components and connections. Freezing temperatures also cause fuel and oil chemistry to change, which can adversely affect engine performance in the future. In addition, inactivity can cause the engine's internal surfaces to rust.
Here are some of the maladies that can befall an unprotected boat during storage:
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Corrosion can occur on internal engine surfaces during storage once engine oil stops circulating and drains away into the pan. Fogging oils help prevent corrosion by forming a protective shield on internal engine components such as pistons, rings, and cylinder walls. These additives are sprayed into the engine prior to storage. Crankcase oil stabilizers perform a similar function, but are poured into the crankcase instead of sprayed directly into the pistons.
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Varnish and gum form in fuel when it is left in fuel systems for long periods of time (especially in the winter). Fuel stabilizers can help keep gum and varnish from forming. these additives are poured into the fuel tank prior to storage.
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Freeze damage can occur anywhere in the engine cooling system or potable (drinking) water system. Because it is difficult to make each system completely clean and dry, antifreeze is used in these systems instead to prevent the water that is there from freezing. By pumping antifreeze through a water system in the fall, boaters can keep the hoses, pumps, tanks and other plumbing from freezing in the winter.
Antifreeze: Your Ally Against Jack Frost
Antifreeze is an additive which, when added to water, lowers the freezing point of the water molecules. The freeze-proof ingredient in antifreeze is either ethylene glycol or propylene glycol. Ethylene glycol makes a good antifreeze/coolant, but is a deadly poison, which makes it dangerous to pets and wildlife and makes disposal problematic. Propylene glycol (PG) is odorless, tasteless, biodegradable, and non-toxic. It's as effective in freeze protection, but is more expensive to produce.
There are three main types of marine antifreeze: potable water system, engine winterizing, and engine antifreeze/coolant, which vary according to the additives in them.
Engine system antifreeze/coolant should never be used in potable water systems, due to the potential presence of toxic ingredients.
Virgin Antifreeze is Best
It’s common to recycle PG which is used in aircraft de-icing, and to sell it for use as marine and automotive antifreeze. Due to the contaminants that may be present, we recommend that you buy virgin PG products that have not been collected off the tarmac of an airport. While virgin PG products cost more, they are worth it, especially if they are to be used to winterize drinking water systems.
Selecting Antifreeze Based on Value
The main thing you pare paying for is the amount of PG in the product. PG levels vary from around 25% to 95%. More PG in the product means you have to use less to achieve a certain level of freeze protection. Products that advertise protection to -50°F may require that you use 100% of their product to reach this level of protection, while other products can be diluted 1:3 with water and still hit -50°F. In other words, you need to know the recommended dilution of the product to reach a desired level of protection, as well as the price, to make a value comparison.
Typical Winterizing Tasks
The following tasks are typical to what boat owners do to winterize a boat. The actual tasks required to winterize your boat will vary according to how it is equipped. Given this, we suggest you create a winterization checklist based on your boat's owner's manual and on how it is equipped. For specific step-by-step procedures, see the list of related articles towards the end of this article.
Start with a Clean Boat: A clean boat will fair better during periods of inactivity and reduce the prep work required when it's time to use it again. Be sure to thoroughly clean and wax the hull, deck, and all hardware and trim. Check fiberglass and gelcoat for damage and make necessary repairs. Also, clean windshields and any fabrics such as canvas covers, Isinglass, and Bimini tops. Dry canvas completely before storing it neatly, preferably indoors.
Flush Your Engine's Cooling System: Giving your engine's cooling system a good freshwater flush to remove dirt and debris, followed up by treating the system with antifreeze is essential to protecting your outboard, inboard or sterndrive engine against freeze damage. West Marine offers a number of Antifreeze Winterization Kits to make this process easy. Kits include our Engine Winterizing Kit and Camco's Inboard/Outboard Winterizing Kit, both of which greatly simplify the winterization process.
Protect Potable Water, Sanitation and AC Systems: If left unprotected, all of these systems can suffer freeze damage. Treating them with PG antifreeze is the best way to ensure against unwanted surprises come spring.
Install a Water Heater Bypass Kit: If your boat has a water heater, installing a water heater bypass kit gives you the ability to isolate the hot water heater from the rest of the freshwater system so it can be emptied independently. This prevents you from having to fill the hot water heater with antifreeze, which is costly but unavoidable without this device.
Treat the Fuel System: Fill the fuel tank with fresh fuel to prevent condensation buildup while your boat is in storage. Replace the fuel filter or install a water-separating fuel filter if you don’t have one. Treat your fuel system with a fuel stabilizer, following the manufacturer’s instructions to prevent gum and varnish buildup. After adding the stabilizer, run the engine for a few minutes to circulate it through the system.
Fog Your Engine: Winter maintenance on outboard or sterndrive engines prevents buildup and protects components during storage. To prevent rust and corrosion, spray fogging oil into the engine where it will coat cylinder walls and other surfaces and protect against rust and corrosion. Fogging oil forms a protective barrier without leaving residue or causing excess smoke when the engine is restarted.
Protect Potable Water, Sanitation and AC Systems: If left unprotected, these systems can suffer freeze damage. As with your engine, treating them with PG antifreeze is the best way to avoid surprises in the spring.
Change the Engine Oil and Gear Lube: Change the oil and filter in inboard engines and four-stroke outboards. Since engine oil drains more easily, run your engine up to normal operating temperature first. Drain and refill the outdrive gear case or outboard lower unit to avoid damage from water and impurities freezing inside. Look for signs of water intrusion in the gear oil, and repair seals if needed.
Lubricate Bearings, Fittings and Hardware: Lubricate all fittings on the sterndrive, steering system, and engine trim mechanism. Use a moisture-displacing lubricant on hinges, latches, and metal parts to protect them. Don’t forget to inspect and grease wheel bearings on trailer boats and apply water-resistant grease to the propeller shaft.
Thoroughly Inspect Your Boat: Take the opportunity to inspect potential problem areas. Look for signs of corrosion, wear, and rough operation in steering and control systems. Inspect fuel lines, hoses, and wiring for any damage or leaks. Tighten hose clamps and check engine belts for wear. Replace any parts, like sacrificial zinc anodes, that show excessive wear or corrosion.
Prevent Moisture Damage: Remove any standing water and debris from bilge compartments, lockers, and storage areas. Clean these thoroughly and use moisture absorbers to prevent mold and mildew. Clean and dry cushions and store them upright to promote air circulation.
Remove Unnecessary Gear: Take off any gear that doesn’t need to remain on the boat during winter. This includes life jackets, ropes, and electronics. Store these items indoors to avoid dirt, moisture damage, and theft. Remove the marine battery, clean its terminals, and store it in a cool, dry place. Check and recharge the battery periodically during the off-season.
Cover Your Boat and Check it Often: For the best protection, store your boat in a climate-controlled space. If that’s not possible, use a high-quality cover. In harsh climates, professional shrink-wrapping offers the best protection, but a custom-fitted cover can work well, too. Make sure the cover is secure and check it regularly for snow, debris, and water buildup. Keep it tight to ensure your boat stays protected.
Winterizing FAQs
Why is winterizing my boat important?
If you keep your boat in an area subject to a hard freeze or even an occasional cold snap, winterizing helps protect your boat’s engine, plumbing, and other systems from damage caused by freezing temperatures, corrosion, and inactivity. It helps to ensure your boat is in top shape when you bring it back to life in the spring.
Do I need to winterize my boat if I live in a warm climate?
If you live in a mild climate like South Florida, where freezing temperatures are rare, full winterization may not be necessary. However, it’s still important to protect your boat against humidity, mold, and general wear during periods of inactivity.
What can happen if I don’t winterize my boat?
Skipping the winterization process can lead to expensive repairs. Water left in your engine or plumbing can freeze and expand, causing cracks and leaks. Fuel can degrade, forming varnish and gum that clog your system, and internal parts can corrode due to condensation.
How do I prevent my engine from freezing?
To prevent freeze damage, run antifreeze through the engine’s cooling system. You can also use fogging oil to coat and protect internal surfaces from corrosion.
What kind of antifreeze should I use?
For engines, use propylene glycol (PG)-based antifreeze for freeze protection. Never use toxic ethylene glycol antifreeze in potable water systems! Always use virgin PG antifreeze to ensure it's free from contaminants.
Can I use recycled antifreeze?
Recycled antifreeze is available, but it may contain contaminants. Virgin antifreeze is more expensive but provides peace of mind, especially for potable water systems, where safety is a top concern.
What is fogging oil, and why do I need it?
Fogging oil is sprayed into your engine’s intake to prevent rust and corrosion on internal metal surfaces during storage. Use it to protect internal engine components during long periods of inactivity.
Should I cover my boat during winter storage?
Yes, covering your boat protects it from moisture, dirt, and debris. Shrink-wrap, which is designed to shed rain and snow, provides the best protection, but canvas covers or tarps can also work well, provided you moniter them closely.
How can I prevent mold and mildew during storage?
Controlling moisture and humidity is essential. Make sure your boat's bilge is dry. Excess moisture can be controlled with dehumidifier crystals. If you choose to shrink wrap your boat, be sure the shrink wrap cover has self-adhesive vents to promote airflow. You can also place low-wattage air dryers in large areas to control moisture.
What are de-icers, and do I need one?
De-icers are small motors that circulate water to prevent ice formation around your boat. If you store your boat in the water during winter, a de-icer helps avoid damage caused by ice forming around the hull or docks.
Conclusion
When the geese fly south, it's your cue to winterize your boat to safeguard it from winter's chill. By winterizing your boat — protecting its engine and systems with antifreeze, fogging the engine to prevent rust, and treating your fuel system — you’ll ensure your boat is ready for a hassle-free start to the boating season in the spring.
We’re Here to Help!
Whether you're getting your boat ready for winter or gearing up for spring adventures, West Marine is here to support you every step of the way. With over 230 stores and a robust online presence, we offer the products, expert advice, and services to meet all your boating needs. Let us help you keep your boat in top shape, season after season.