Our top 7 tips when winterising your boat

Keeping a boat protected from the elements during the winter is one of the most important annual maintenance tasks for boat owners. Winterising your boat is a must as it will help you to protect your asset, save money on repairs on the longer term, and will make the relaunch in spring a whole lot easier.

If you prefer to get some help with these steps, we recommend booking engineers and maintenance services early so that winter won’t catch you by surprise. Engineers can help with all elements of winterising engines and domestics, engine servicing, and re-commissioning in spring, giving you total peace of mind.

If you enjoy maintaining your boat yourself, are new to boat maintenance or need a refresher on how to winterise your boat, read on! Our handy guide fills you in on the basics you need to know.

Our 7 top tips on prepping your boat for winter

1. If you only do one thing, winterise your engine*

If you follow good maintenance protocols before your boat goes into storage, it can sit for a few months or even longer. There is a lot you can do to protect a boat engine while it’s idle and lifted during the colder months of the year.

Inboard engines

Here are the essential maintenance steps to keep your inboard engine in good condition over the winter months.

Step 1: Change the oil and fuel filters – run the inboard engine to warm the oil before you do this. Changing the oil is important because old engine oil gets contaminated with combustion by-products, so if left in, it will shorten the engine’s life.

Step 2: Check coolant concentration (use an antifreeze tester). Flush existing water out of the raw water cooling system and then flush it with a coolant mix. Use a suitable biodegradable antifreeze. Different engines have their own cooling systems so each type of engine should be winterised differently.

Step 3: Look after rubber components. You can remove alternator belts for the winter period which helps them retain their shape and prolongs their life. Left in, they will be set in a stretched form for a long period. Part of your service schedule will to be to replace belts and impellors.

Step 4: Change the gear oil (especially if it looks cloudy) and check the stern seal – make sure there are no leaks or drips (in which case the stern seal will need adjusting or replacing).

Step 5: Check and dry the bilges beneath the engine to prevent corrosion. You may wish to paint the bilges white so that future drips or leaks are easier to spot.

Step 6: If your boat is staying on the water, ensure seacocks are winterised and firmly closed, so they don’t leak out. If your boat is going ashore, leave seacocks open.

Step 7: If you have a diesel engine, fill your fuel tank to the brim to avoid condensation. Filling the tank with fuel helps to prevent the growth of diesel bug. Some boat owners choose to use a fuel treatment to prevent this.

Be aware that diesel bug exists where there is water. It is essential to drain water out of the tank if it appears.

Outboard engines

Outboards are a lot simpler to prepare for winter, although they do still require regular servicing too.

If you have an outboard engine, flush it with fresh water using a bellows attachment and wash it down with mild detergent. Then lubricate the cylinders and the engine exterior – lubricate the cylinders by running a fogging agent through the carburettor.

If the petrol tank is small, empty it (responsibly), and refill it in the spring. For larger petrol tanks, just top up with fresh petrol in the spring.

Check the seal on the fuel cap. Smear Vaseline onto the fuel filler cap to prevent any rainwater from getting in.

Top tip: when checking your engine and carrying out maintenance, use a torch to get plenty of light and a portable inspection mirror so you can see under and behind things.

See more top tips for maintaining a boat’s engine here.

2. Winter-clean the boat interior

It’s best practise to remove any excess equipment, including soft furnishings. Give the interior a thorough clean, including any kitchen appliances. Leave the cupboard and internal doors ajar (including the fridge/freezer) so that air can circulate and no nasty odours get trapped inside.

Consider using a 240v dehumidifier set on a timer in any inside space if your winter mooring or boat storage includes an electricity hook-up. Or leave moisture absorbers inside if you have no source of power. Otherwise, a lack of ventilation will almost certainly cause mould.

Wash and dry linen, soft furnishings, blankets, curtains, and any clothing, and store them ashore/at home. Soft furnishings will likely become damp and pick up mildew if you leave them on board.

3. Drain plumbing

Empty fresh water tanks, draining down your boiler and disconnect your pump. Blow through pipework taps and the shower head to push out any further water, winterise your toilet, and leave taps open. Pump out any holding tanks.

4. Wash the boat exterior

Salt and dirt need removing, so pressure-wash the bottom, topside and decks. Be sure to remove any barnacles or weed growth. If your boat is being stored on land over the winter, take this opportunity to do a thorough check of all the parts that are normally submerged in water or are difficult to get to including, outdrives, rudders, propeller and shaft, anodes and skin fittings.

5. Apply a wax coating

Apply a wax coating to the exterior after cleaning to protect any exposed parts against bad weather.

6. Remove batteries and store

If your boat has lead acid batteries then it’s recommended to remove these batteries from the vessel and lightly grease the terminal ends. Store batteries in a cool, dry place during the winter months. A garage is ideal and will ensure your batteries don’t freeze (which they would if they were kept outside). Keep batteries topped up and charge them monthly (or use a trickle charger). Remember, batteries left uncharged for extended periods may need to be replaced.

If you are unable to remove batteries, keep them full and regularly charged, and disconnect them from the electrical system before leaving them.

7. Boat storage

It is advantageous to store your boat undercover and out of the water throughout the cold winter months. If that isn’t possible, cover your boat with a proper fitted cover or tarpaulin.

This isn’t an exhaustive list; there will be additional things you may need to consider depending on the type of boat you have and how it will be stored. However, this should be enough to get your boat winterising task list going.

Annual mooring with Val Wyatt

Our annual mooring at Chichester and Wargrave includes winter hard standing, lift, chock, and re-launch. Undercover winter storage is also available to mooring holders for a surcharge. We can provide winter hardstanding outside or under cover for boats not moored with us.

Our add-on services include boat lifting, pressure washing, antifouling hulls, fitting winter covers, compound polishing and more.

If you would like more information, you can learn more about our services here.

Comprehensive boat maintenance all year round will ensure your boat operates at peak performance and stays in great condition. See our top tips for general boat maintenance here.

*Disclaimer

The information provided in this blog about winterising boat engines is intended as a general guide only. For optimal safety and to prevent potential damage, all maintenance and winterisation work should be carried out by qualified professionals. Attempting to perform these tasks without the necessary expertise may result in engine damage or personal injury. Always consult with a marine specialist for the best results.

For further information on our boat brokerage, mooring and boat storage services, contact our expert team by calling 01189 403211.