Failure to winterize your boat can result in corrosion, cracked engine blocks, boasted hoses and cracked hulls. Repairing damage caused by winter weather can get extremely costly. Preparing your boat from the grips of winter requires you to perform some basic maintenance in the fall of the year before the temperatures dip below the freezing mark. This is a little more complex than winterizing your vehicle and involves a few additional steps that start at the bow and continues to the stern.
Boat engines are different than other engines. They may operate on gas and need oil, but special care must be given to ensure they are winterized properly. To keep your boat engine from freezing, free from corrosion and ready for spring action, the first thing you should do is consult the owner’s manual. This will have detailed instructions on what must be done to secure your motor for winter.
Typically this will involve removing the engine cover and inspecting all hoses and wires. If the wires appear frayed and, hoses appear soft and have cracks, replace them. Check any belts and ensure they are free from cracks. It may also be recommended to adjust the tension according to the manufacturer’s specifications.
Visible nicks and scratches should be painted to prevent corrosion, and you should also change the engine oil and filter. Some engines must be flushed with fresh water before storage. Be careful when performing this procedure because all water must be drained before winter storage because even a small amount of water can freeze and cause damage to the engine.
Ensure your inboard or stern-drive engine antifreeze is filled to prevent freezing. It may be advisable to replace this with new antifreeze each season as a precaution. Add fuel stabilizer to any remaining gas to the tank and run the engine for a few minutes allowing the treated gas to circulate. This will help prevent the clogging of jets and injectors.
Once you have completed this, use fogging oil and spray it into the carburetors while the engine is running. Turn off the fuel supply and wait for the engine to stop. This will burn off any fuel left in the system. Then remove the plugs and spray some fogging oil in the cylinders and rotate the engine manually a few times to ensure the oil penetrates through the cylinder. For yamaha engines please use specified Yamaha Boat Oil.
Replace the spark plugs and open the carburetor drain. This will remove the last bit of fuel that may be present in the system. Using a block of wood, raise the engine and remove the prop. Inspect it for damage and debris. Lubricate any moving parts as per the owner’s manual and replace the prop.
For some engines, it may be a good idea to inspect the gear case and gear lube. Should you notice the oil is milky in color, this may indicate water has penetrated the gear box. You may also want to inspect the oil for metal chips which could indicate problems with the gears.
Replace the oil accordingly and your engine has now been properly winterized. Taking the time to properly winterize your boat engine means a quick launch come spring and years of enjoyment as you cruise around the water in your boat.