Best Boating Practices: Winterizing your Boat and Outboard – On The Water
Boaters in the Northeast don’t have the luxury of a year-round season, so we make the most of the time we do have. When spring finally arrives and stripers return to our coast, we want to get out on the water without being held back by maintenance or mechanical issues. The key to the dream of a trouble-free spring commissioning is proper boat winterization in the fall.
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Why Winterize Your Boat?
Water is the enemy of winter boat storage. When temperatures drop below freezing, water expands, and the power of freezing water can crack hoses, pumps, seals, engine parts, and even hulls. If you’re storing your boat outside in freezing weather, there are winterization steps you must take to protect it from extreme conditions.
How To Winterize a Boat for Outdoor Storage
- Drain Water from Systems
Drain all water from the bilge, livewells, and freshwater systems, as any water left inside can freeze and expand, leading to cracked hoses, pumps, or even hull damage. If your engine has an internal cooling system, use marine antifreeze to prevent freezing. Make sure to run antifreeze through the system to protect it fully.
- Remove Batteries
Disconnect and remove all boat batteries. Cold temperatures can damage batteries, and freezing can cause them to lose charge or even crack. Store them in a warm, dry place and keep them charged to extend their lifespan.
- Protect the Interior
If your boat has an open cockpit or cabin, take out any removable cushions, electronics, or valuables and store them indoors. Moisture and freezing temperatures can cause damage to fabrics and electronics. Wash all cushions with a vinyl cleaner before storage to prevent mold and mildew from forming.
- Inspect and Protect Seals and Gaskets
Check all windows, hatches, and doors for proper seals. If seals are worn, water can enter and freeze, causing further damage. Replace any compromised gaskets.
- Properly Support the Boat
Ensure your boat is supported properly on a trailer or jack stands to prevent warping of the hull over time. Keep the boat slightly tilted to allow water to drain from any areas that may collect rain or melted snow.
- Cover the Boat
If you’re not using shrink wrap, use a heavy-duty, well-fitted winter boat cover designed for your boat’s size and shape. Ensure the cover is secured and that water won’t pool on top, as freezing water can cause damage.
- Ensure Proper Ventilation
Whether covering or shrink-wrapping your boat, make sure vents are installed to allow airflow. This will prevent moisture buildup, which can cause mold, mildew, and corrosion.
- Fuel Tank Considerations
Either drain the fuel tank or fill it to around 95% full and treat it with a fuel stabilizer. This prevents condensation and reduces the risk of fuel degradation over the winter.
Winterizing an Outboard Motor
Winterizing an outboard motor is essential to prevent damage from freezing temperatures and ensure the motor runs smoothly when you’re ready to use it again in the spring. Note that exact procedures may vary by manufacturer and model, so it’s important to consult your specific model’s owner’s manual for winterization recommendations.
- Flush the Engine with Fresh Water
To remove any salt, dirt, or contaminants, attach a flushing device (earmuffs) over the water intake, connect a garden hose, and run the engine for about 10-15 minutes to flush out the cooling system.
- Stabilize the Fuel System
Add a fuel stabilizer to your fuel tank to prevent fuel breakdown and gum buildup in the carburetor or injectors. After adding the stabilizer, run the engine for a few minutes to ensure the treated fuel circulates through the entire system. For EFI (Electronic Fuel Injection) or V6/4-stroke engines, this step is crucial, as fuel varnishing can damage sensitive components.
- Fog the Engine (for 2-Stroke and 4-Stroke)
Fogging oil protects internal engine parts from corrosion and moisture. Spray fogging oil into the carburetor or remove the spark plugs and spray directly into the cylinders while the engine is running (for a short period).
- Drain Water from the Engine
Tilt the outboard down to drain all water from the cooling system. This step is critical to prevent any water from freezing inside the engine.
- Change the Engine Oil (for 4-Stroke Engines)
Change the marine outboard engine oil and replace the oil filter to remove contaminants and water that might have accumulated during the season. Drain and refill the lower unit gear oil to prevent water contamination from freezing and damaging the lower unit.
- Grease Fittings and Lubricate
Apply marine-grade grease to all grease fittings (like the steering cable, propeller shaft, and any other moving parts). Lubricate control cables and pivot points with corrosion-inhibiting lubricant.
- Check and Replace the Anodes
Inspect and replace any corroded sacrificial anodes. These protect your motor from galvanic corrosion in saltwater environments.
- Remove the Propeller (Optional but Recommended)
Remove the propeller to check for fishing line or debris that could damage the seals. Store the propeller separately and apply grease to the propeller shaft before reinstallation.
- Battery Maintenance
Disconnect and remove the battery. Store it in a cool, dry place, and occasionally charge it over the winter to maintain its lifespan.
- Cover and Store the Motor
Use an appropriate outboard motor cover to protect the motor from dust, moisture, and pests. If storing outdoors, ensure it’s well covered and in a dry location.
Boat Winterization Shopping List:
- Fuel Stabilizer: Yamalube Fuel Stabilizer and Conditioner Plus
- Fogging Oil: Star Brite Fogging Oil
- Oil & Oil Filter: Engine Oil and Oil Filter
- Fuel-Water Separator: Fuel Filters
- Gear Lube: Yamalube Marine Gearcase Lube
- Grease Gun & Marine Grease: Quicksilver Marine Grease
- Antifreeze: West Marine Marine Antifreeze
- Dehumidifier: Star Brite No Damp
• Check out the West Marine Boat Winterization guide for more helpful advice and all the products you need for a successful winterization and a trouble-free spring.
