How to Winterize a Boat For Storage

When the weather cools and boating season winds down, it’s time to give your boat a little TLC before putting it away for the winter. Who you need to winterize your boat? It helps you stash your boat properly so it’s shipshape when spring rolls around. Think of it as a seasonal tidy-up with some mechanical muscle.

Here’s your simple, step-by-step guide to winterizing your boat before you pack it away in self-storage.

Clean It Like You Mean It

Start with a full interior and exterior spruce-up. Wash the hull, clean out compartments, and remove any gear and electronics that don’t need to hibernate onboard. Mildew loves moisture, so take out fabrics like life jackets, cushions, or rugs and let them dry out somewhere warm.

It’s also a good idea to apply a rust inhibitor on your metal, and steering and control cables. Be sure to remove plants or barnacles from your stern drive, and investigate for cracks or holes so your boat is in great condition before you close those storage doors.

Pro tip: Give your boat a solid wax on the outside and a mildew spray down below.

Drain the Fluids

Water left in your boat during freezing temps can cause some serious damage. Make sure you:

• Drain the bilge
• Empty the water tanks, manifolds, and coolers
• Run antifreeze through plumbing systems (sinks, showers, toilets)

Don’t forget the engine! Follow your boat manufacturer’s guidance for flushing it out and replacing water with marine antifreeze.

Prep the Engine

Here’s where things get technical but manageable. You’ll want to:

• Change the oil and oil filter
• Replace the fuel filter
• Fill the fuel tank and add a fuel stabilizer
• Run the engine briefly to circulate the stabilized fuel (make sure this is done outside or in a ventilated space and not in your storage unit)

This keeps your engine from gumming up while it’s packed away. It’s also the time to fog the engine (a spray you use to coat internal parts) if your manufacturer recommends it.

Disconnect and Remove the Battery

Remove the battery and store it separately in a cool, dry place. Loose batteries cannot be stored in Public Storage units.

To avoid the battery wearing down, use a trickle charger. Smart or automatic trickle chargers (also called battery maintainers) are a great choice for long-term storage. They automatically sense when the battery needs a charge and stop when it’s full, cycling on and off as needed.

Cover It Up and Put It Away

A good boat cover (fitted, vented, and waterproof) keeps dust, critters, and moisture out. If you’re storing indoors in a self-storage unit, this is the last touch before you stash it away for the season. Leave a few moisture absorbers inside to keep humidity in check. Baking soda placed throughout the boat can also help to absorb moisture.

Winterizing might sound like a chore, but it’s just a few clear steps between you and smooth sailing next year. From draining and drying to storing it the right way, you’re not just putting your boat away—you’re setting it up for a better season ahead.

(You cannot store anything worth more than $5,000 in a Public Storage unit.)