Say It Ain't Snow

By Michael Vatalaro

A quick bit of planning now will make winterizing your boat go smoothly this fall.

Photo of a marina in winter

As depressing as it might be to start thinking about winterizing and the end of the boating season in early fall, trust me, it was way more depressing writing about it in July when this article was due. But thinking now about how you will tackle putting your pride and joy away at the end of the season can save you time and hassle, particularly if you are like me and you put off the actual deed until the weekend before Thanksgiving. Five major areas of concern are: Exterior Protection, Interior Moisture Control, Engine/Outdrive Maintenance, Trailer Maintenance, and Electronics/Batteries.

Exterior Protection:

Believe it or not, it's time to wax again. A late-season coat of wax will help your boat shed dirt and grime all winter long. After you've washed and shined your boat, you'll need to cover it to keep the elements at bay. A custom winter cover is a great investment, but many boaters also find the semi-custom covers like those from Taylor Made to be effective ( Or you can shrinkwrap your boat yourself. You can get all the supplies you need at or at your local West Marine.

Interior Moisture Control:

Mold and mildew both need moisture to grow. One of the ways to combat moisture is to put proper venting in your winter cover to allow the interior of your boat to "breathe" as it heats up and cools down each day and night, and to leave hatches and locker doors ajar. The other is to put moisture control systems in place such as chemical desiccants like DampRid or Star brite's No Damp. You can also pretreat problem areas like your boat's air-conditioning ducts or enclosed lockers with Pic Organic's "M" a marine-grade mildew and mold killer. This aerosol product is enzyme based, so it keeps killing as long as you don't wipe it off. Spray it on in the fall, and it should keep working all winter long. And because it's an aerosol, you can "fog" your boat or the AC ducting to keep mold and mildew from growing in places you can't reach.

Engine/Outdrive Maintenance:

Winter poses the greatest threat to your engine, its lower unit, or your outdrive. Freezing temps can easily crack a block or gear casing if you haven't taken proper precautions. Obviously you need to winterize by doing an oil change and lower-unit oil change, and replace any water in cooling passages with antifreeze (see our Seaworthy article "Winterizing Must Do's"). The oil changes prevent the acids and other containments from a season's worth of engine hours from attacking internal components while removing any water that may have found its way into the lower unit, which if left behind could cause freeze damage. And don't forget to winterize the head if you have one.

Remember, the temperature ratings on nontoxic antifreeze (-50 degrees F, for example) are for burst protection, meaning the temperature at which enough ice will form to bust a copper pipe. Antifreeze rated at -50 degrees F actually starts to freeze at around 16 degrees F. If you live somewhere with winter temperatures that fall below zero, you may need -100 antifreeze.

Trailer Maintenance:

This is a great time to test your lights and replace any spotty connections, and take the time to give the trailer a good hard look, lubing and spraying protective silicon-based lubricants along the way (see our Seaworthy Winterizing checklist for more details). Ideally, you should also jack up the trailer so that the wheels are an inch or two off the ground to prevent dry rot and flattening of the tires during the off-season. Removing the coupler from the trailer tongue makes it much harder for someone to steal your rig.


Just like the rest of us, batteries don't like being cold. A deeply discharged battery or one that has lost a lot of electrolyte can suffer damage in cold weather that will severely shorten their useful life. If yours are easy to remove, bring them indoors. If not, make sure the electrolyte is topped off using distilled water, and that they are fully charged. If possible, put them on a charger once a month during the off-season to keep them from becoming too deeply discharged. This is also a good time to clean the battery terminals with a stiff wire brush.

If your electronics are binnacle mounted, bring them inside also, if for no other reason than so prevent theft. Cover the loose connectors as well.

These simple steps will go a long way toward preventing any nasty surprises when the time comes to launch in the spring. 

This article was published in Fall 2012 issue of Trailering Magazine.

Shopping List

Photo of winter boat cleaning products

  • Boat wash and wax (plus rags, pads, or polish cloths)
  • Mildew control
  • Oil and filter(s)
  • Lower-unit oil
  • Shrinkwrap film, vents, straps, and snaps
  • Distilled water
  • Antifreeze
  • Penetrating lubricant
  • Wire brush


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