How to Store Your Boat Over Winter

‘Winterise’ Your Boat

As the boating season winds down, it’s time to start thinking about properly storing your boat for the winter months. Doing a bit of preparation now can save you a lot of headaches come spring. (The Tamaki Marine Park team hear plenty of stories about boats that don’t go after winter!) With that in mind, here’s what you need to know:

Engine Maintenance

The engine is one of the most important areas to focus on when storing your boat. Stale or water-contaminated fuel can cause all sorts of issues, from starting problems to loss of power.

• Flush the engine with fresh water using muffs or a flushing port.
• For carbureted engines, spray fogging agent into the air intakes and let the engine burn off the fuel in the lines.
• Remove the spark plugs and spray fogging agent into the cylinders to coat the interior surfaces.
• For inboard engines with closed cooling systems, flush with antifreeze. Outboards need to be stored upright to prevent water damage.
• Change the engine oil, transmission fluid, and fuel filters before storage.

Exterior & Trailer Prep

Good boat storage isn’t just about the engine – you also need to take care of the exterior and trailer.

• Wash the hull thoroughly and inspect for any damage or growth. Also consider waxing or applying a protective coating.
• Clean all through-hull fittings and open any drain plugs to allow the boat to fully drain.
• If storing the boat on a trailer, ensure the tires are properly inflated and the wheel bearings are well-greased. Move the trailer periodically to keep everything moving.
• Tilt the trailer slightly bow-up to allow water drainage.

Interior Storage

Just as important as the exterior, you’ll want to prepare the boat’s interior for storage.

• Remove all loose gear, cushions, and other items that could get damaged or cause mould/mildew.
• Prop up cushions and mattresses to allow airflow and prevent dampness.
• If shore power is available, run a dehumidifier periodically to control moisture.
• Charge the batteries and turn off all electrical systems.

Moored or Marina Storage

Boats kept in the water over winter face their own unique challenges. In addition to the tips above:

• Top up fuel tanks to minimise condensation, and add a biocide for diesel engines.
• Change engine coolant and oil for inboard engines.
• Flush raw water cooling systems, and seal any openings to keep moisture out.
• Regularly visit the boat to check batteries, run the engine, and air out the interior.

Storing your boat properly is essential to ensure it’s in tip-top shape when you’re ready to hit the water again next season. By taking the time for some basic maintenance and preparation, you can rest easy knowing your vessel is protected over the winter months.