1. If your engine is raw water cooled, when draining your cooling water don’t forget to run your engine until it is hot then flush it through with a strong solution of antifreeze until this has come out of the outlet for some time. It is preferable to remove the thermostat first so that the antifreeze gets into the engine-cooling jacket. If you do this with a cold engine then the thermostat will be closed and parts of the cooling system will not be flushed with antifreeze. Also don’t forget that only around 10% of the cooling water goes through the gearbox cooling system so make sure you run the antifreeze for some time to make sure that it gets there. If you don’t then you may find that you have a cracked gearbox case in the spring. If your engine is fresh water cooled then don’t forget that there is still raw water in the system heat exchanger so it is still wise to suck antifreeze through the water inlet even though you may have it in the fresh water reservoir.
2. It is a good idea to change your engine oil before winter. All those corrosive contaminants in your oil will spend all winter attacking the innards of your engine. The protective additives in new oil are broken down after a relatively short time (particularly in diesel engines) so a coating of new oil around the engine will protect it from corrosion over the winter period. A good dose of WD4O or similar over the exterior of the engine will perform a similar function on the outside and on the engine electric’s. Some people recommend starting the engine occasionally to redistribute the oil.
3. Remove the impeller from you water pump. If you don’t then it will take up a permanent ‘set’ and when you come to start the engine next year you may find that your water pump does not work and the engine overheats. If you can’t or don’t want to do this then turn the engine over manually occasionally to change the position of the impeller blades. This will discourage the ‘set’.
4. Try to get all of the fresh water out of your drinking water system including water heaters and pumps. Frozen water expands with terrific force and can easily destroy your freshwater pump or calorifier. As a further precaution you could lag these items with insulation. One solution, which may appeal to some, is to pour a bottle of cheap vodka (or gin to taste) into your fresh water tank after you have drained the water out. Flush this through the system a few times to make sure it is evenly distributed. I know this sounds like a wind up but alcohol is the main constituent of antifreeze and this tastes better. It also gets next season off to a good start!
5. If you can get the water out of your stern gland by squeezing it (when it is out of the water) then so much the better. Ice expansion here can cause your stern gland to leak by damaging the soft material, which ensures a close fit on the prop shaft. When you put your boat in next year you may find that it seeps.’
6. Any water in your loo pump may freeze destroying the pump body. Pumping a weak solution of antifreeze through the toilet will stop that happening.
7. Flies love to hibernate in your sails and will infest you boat given half a chance. Having said that ventilation is imperative if you want to discourage mould. Solution- remove your sails to home and tape some net curtaining over ventilators.
8. Try to fill any splits or cracks either in the wood or the fibreglass before leaving the boat. If water gets in and freezes then it will expand and cause sever cracking. If the water gets through the gel coat and into the mat layer then severe damage could result. This would be costly to repair.
9. I find that dehumidifier crystals work quite well in minimizing damp from the boat. They removed almost three pints from my boat last winter, that must be worth it!
10. For those of you who have trouble with boat electric’s I have found this guide useful www.islandnet.com
Please note:- These are the kind of things I do to winterise my boat and I have found they work for me, however, neither the club nor I accept any responsibility for any damage howsoever caused by following these tips.