How to winterise your boat engine
Before starting to prepare your boat engine for winter, it needs to be warmed up. You can do this retrieving the boat from the water or on dry land by using a flush bag.
Oil and oil filter
Next, it’s time to change the oil in the engine and driveline. Use an oil specified by the engine manufacturer. Also take the opportunity to change the oil filter and lubricate its gasket. If your outboard or inboard motor runs on petrol or diesel, you should also check the spark plugs, clean or replace the fuel filter, and empty the water separator. If you have the time, your engine will also benefit from getting a thin oil film on the cylinder walls.
Check the antifreeze
If your boat engine is fresh water cooled, you should first drain seawater from the cooling system. Then run fresh water with a 50% glycol mixture through the system and leave the mixture in. If the engine is saltwater cooled, flush the system with fresh water, drain it of cooling water and then run a 50% glycol mixture. Leave the mixture in the system after running it through.
This is a general description of what you need when winterising your boat engine. Read more about what applies to your boat engine in the owner’s manual or in the information from the manufacturer.
Frequently asked questions about boat motor care
