Winterizing Your Boat: Do's and Don'ts

The checklist for winterizing a boat can be a long one, with items that might be easy to forget. We've already covered how to winterize a 2-stroke outboard and a 4-stroke outboard, so here we'll be touching on some additional "do's" and "don'ts" for winterizing your entire boat properly. 

Boat winterization tips

Some of the boat winterizing process is common sense. However, little things often get overlooked that can lead to problems down the line. Here's a quick list of 10 things to keep in mind when winterizing your boat.

Buy Do It Yourself winterization kit

Mercury QuickStore fuel stabilizer

Boat Winterizing Do's

Do Run a Carburetor Motor Dry

Run the engine dry if your motor has a carburetor (or carburetors). Draining the carbs is easy to do, but also easy to forget when winterizing your boat. 

Winterize boat motor carburetors

To dry your carburated engine, just disconnect the fuel line and run the engine until it dies to ensure there is no gas left in the carb or carbs.

NOTE: If your motor uses electronic fuel injection (EFI), do not run the engine dry. 

Do Install Permanent Water Heater Bypass

When winterizing your boat's potable water system, it's always best to bypass the water heater. This will save you a couple gallons of antifreeze. Seasonal bypass kits are cheap, but you have to remember to remove them when de-winterizing your boat. Permanent bypass kits, on the other hand, cost a little more but spare you the trouble of having to install and remove them when you winterize/de-winterize. 

Do Use Plumber's Tape

Using polytetrafluoroethylene tape, or "plumber's tape", on all threaded fittings prevents them from leaking, which can lead to ice damage during the winter. Plumber's tape is also known as sealing tape and Teflon tape. 

Do Monitor Your Boat Regularly

Just because you spent hours carefully winterizing your boat, it doesn't mean you can leave it unattended for months. Boat covers and tarps can spring leaks, and you'd be surprised how many destructive critters want to make themselves at home in your boat during the winter. Check your boat at least once a week, even after it's been winterized.

Winterize boat regular checkup

Do Add Antifreeze to the Bilge

The bilge is an often unpleasant and overlooked area. If you don't want to get down and dirty by cleaning out the bilge as part of the winterization process for your boat, add a splash of antifreeze to the bilge to reduce the chances of it freezing.

Boat Winterizing Don'ts

Don't Over-Tighten Threaded Fittings

When you winterize your boat, you'll have to disconnect various pipes and hoses. Don't over-tighten threaded fittings when reconnecting pipes, particularly plastic ones. Plastic tank threaded fittings are already fragile, and can become particularly prone to cracking when they're cold. Go easy on those threads when tightening fittings.

Don't Run an EFI Engine Dry

If your motor has electronic fuel injection (EFI), don't run it dry. An EFI engine doesn't have a carburetor, so there's nowhere for the gas to collect and leave behind unwanted deposits, and therefore no need to disconnect the gas line and run the motor dry. In fact, running an EFI engine dry clogs the intake with oil because the oil won't stop when the gas runs dry. 

Don't Empty the Fuel Tanks

Folks used to drain their tanks when winterizing their boats because the fuel would go stale. However, fuel stabilizers today can easily keep fuel fresh over the winter. An empty or partially filled tank is prone to condensation buildup, especially in winter, which causes corrosion. Brim those tanks before winterizing your boat, and add a quality fuel stabilizer.

Don't Use Portable Electric Heaters

It's hard to believe there are people out there who think using a portable heater is a sensible alternative to winterizing their boat. They must not read the news! Unattended electric heaters are fire hazards that make headlines every year. We're sure there are plenty of marine insurance claims out there too that prove portable heaters are bad news for your boat!

Don't Forget to Remove All Perishable Goods

One of the crew admitted to having proudly winterizing his boat, only to be mortified in the spring at the discovery of a putrid sandwich he left in a storage locker all winter long. Apparently the stench lingered on for weeks! Make sure you get rid of any perishable goods before storing your boat away for the winter.

Boat winterization perishables

We hope these dos and don'ts come in handy when it's time to winterize your boat. A winterized boat is more likely to start up with no issues come spring, so show your craft the offseason TLC it deserves.



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