7 Secrets to Winterizing Your Boat

Unless you live south of, say, Jacksonville, Florida, chances are you will find it necessary to winterize your boat until the first few hints that spring is back for good. Of course that’s a longer time frame in some parts of the country than others, but generally, you’re looking at about the same decommissioning procedure whether it’s two months or six months.

Trailer a Boat

Let it be known that the sure-fire best way to make sure your boat is prepped and stored correctly is to take it to your local dry-storage marina and say goodbye until after the vernal equinox. But us boaters are known to be a hands-on, do-it-yourself breed, so consider the following tips if you’re taking on the task yourself (or with an able-bodied crewmate). Chances are you might just save yourself a little folding money in the process, and IF spring comes early...you’ll be ready to launch as soon as boating fever strikes.

This is not a comprehensive list of the proper steps to winterize a boat. After all, there are lots of different kinds of boats, in both freshwater and saltwater, with both gas and diesel motors, in many different styles. Please check your engine manual for a step-by-step checklist for your particular motor. That being said, here are some tricks of the trade to keep in mind.

Write It Down

It is one of the great fallacies among recreational boaters that will be able to remember exactly what we did to our boat during the winterizing process. But months go by and you find yourself wondering if you really DID change that oil and filter. After all, there’s a reason that we have ship’s logs. So, no matter how good your long-term memory, keep a notebook to remind yourself of what you did and DID NOT do, so you can hit the water running in the spring.

Watch Your Gas

It’s critically important that you add some sort of premium gas stabilizer to your tank after your final outing of the season. Simply fill up not-quite-to-full on your way home (either to the marina or to the launch ramp), add the appropriate amount of stabilizer (brands vary on the ratio), and let the final ride mix thoroughly.

Change Is Good

It’s been a long, enjoyable boating season, so it’s time to treat your boat’s motor to a well-deserved oil change. Depending on the location of your oil pan drain (or dipstick position if your engine has its own oil management system), pump/drain as much of your oil out as possible. This is also the time to change your oil filter, water/fuel separator, in-line filters, and whatever other changeable component you can change. If you do all this now, you will know exactly when something was changed last.

Hold Your Spark

About the only changeable components you want to save for spring recommissioning are your spark plugs. There’s no reason for new spark plugs to sit languishing in a cold engine all winter. However, go ahead and buy your new set while you’re buying all of your filters. Verify that you’ve got the right size by comparing them against the ones already in your engine.

Muff And Fog

Unless you’ve got a closed cooling system (like your car), you will need to make absolutely sure you’ve got water available to run through your motor when you’re decommissioning for the season. This is typically accomplished by using Muffs (aka Rabbit Ears) on an I/O drive or a flushport hose connection on an outboard. Do NOT run your engine without water circulating or you may be decommissioning for good. The next step (on fuel-injected engines) is to crank the engine (not start) and spray a preservative (aka Fogger) into each cylinder via the spark plug port. If you’ve got a carbureted engine, spray the fogging compound into the carburetor with the motor running (with water circulating) until the engine chokes and stalls. You’re trying to distribute the fogger completely throughout the engine.

Smart Battery Care

Make sure you remove your battery before stowing your boat away. However, make sure it’s the very last thing you remove from the boat, because if you don’t, you will have forgotten to raise your outboard or outdrive to the up or trailerable position. Now, store that battery in a warm, dry place like a climate-controlled basement or garage, preferably somewhere close (but not too close) to an electrical outlet. This will give you an easy way to put your battery on a trickle charger about once a month to have it ready to go.

A Final Word About H2O

Without a doubt, the single most potentially damaging thing to your boat in the off-season is, ironically, water. It will go where it can and lead to things like mold and mildew (and the accompanying smells) and it do serious harm if allowed to find its way into tight areas and expand as it freezes. Do yourself a favor and invest in a great cover with an internal bracing system. Better yet, pony up for a quality shrink-wrap job. And when you park your boat for the winter, make sure it’s tilted as much toward aft as possible to allow water to do its thing and run down hill.

Read more tips on boat maintenance.