Winterizing Your Outboard
By Paul Esterle
As much as we hate to admit it, many of us in northern climes are putting our boats and outboards away for the winter. Many boaters don’t pay much attention to winterizing their outboard motors. Many of those same boaters are looking for mechanics in the spring to find out what’s wrong with their engines.
Winterizing your engine is as much about the next season as it is about the coming winter. Part of the winterizing work is to prevent winter damage while the remainder is preparation for a good start to the summer.
Oils and Filters
Now is a good time to replace the oil in your engine or outboards’ lower unit. Most lower units or gear cases have an upper plug and a lower plug. Remove both to completely drain the oil. Check the oil as it’s draining out. If it looks like coffee with milk in it, you probably have a water leak somewhere, schedule some time with your mechanic to sort the problem out. Do it now; If you wait till the spring he’ll be buried and you’ll be frustrated instead of boating.
Refilling most lower units is counterintuitive. You put the oil in the lower drain plug until it oozes out of the top drain hole. Screw in the top plug while the oil container of pump is still in place in the lower drain hole. Trying to refill the lower unit from the top drain hole will practically guarantee that you won’t get enough oil in there.
While you are working around the outboard, apply grease to any grease points and lubricate any places that need it. Refer to your service manual for the proper lubricants and lubrication points. A good manual may save you an expensive repair bill for missing an important point.
Outboard engines are cooled by taking in water from outside the boat, pumping it through the cooling circuit and then dumping it back into the water. Antifreeze needs to be run through the engine to provide protection against freezing and consequent engine damage. Two main types of antifreeze are used in marine engines, one with a slushing temperature rating of -60 degrees and the second good to -100 degrees. These antifreezes differ from the standard pink marine and RV antifreeze designed for drinking water systems in that they contain more anti-corrosion chemicals to protect the engine. These antifreezes should be used directly from the bottle and not diluted. Both antifreeze types are non-toxic and can be run through the engine cooling system and dumped on the ground. Under no circumstances should automobile antifreeze be used in this way, it is toxic to animal life.
Before all this antifreeze starts flowing, however, it is important to run the engine long enough to ensure that the thermostats open up. Running the antifreeze through a cold engine will guarantee that some areas of the cooling circuit won’t get protected.
Some folks also pull the rubber impellers out of the pumps for the winter season. They feel that removing the impeller will keep the vanes from developing a bend or set. This is by no means a universal practice but it can’t hurt – unless you forget to put them back in the spring.
Store the engine upright so any remaining water will drain from the unit.
Fogging an engine refers to the practice of spraying fogging oil into an engine to protect the moving parts; rings, pistons and valves for example. These fogging oils can be sprayed into the carburetor while the engine is running or it can be applied through the spark plug holes while the engine is slowly turned over.
Do not spray fogging oil into the intake of an EFI (Electronic Fuel Injection) engine. Instead an oil mixture should be run through the fuel lines into the fuel injection system.
The advent of E-10 gasoline and the attendant ethanol problems has created a lot of confusion about winterizing fuel systems. The ethanol in the fuel has an affinity for water and, when the amount of water in the fuel reaches a critical point, the fuel water and ethanol will “phase separate” into bad gasoline on the top and water/ethanol on the bottom. Once the fuel has gone through phase separation it cannot be recombined and must be pumped out and properly disposed of.
The solution to winterizing fuel tanks is to either empty them completely or fill them up to about 95% of capacity.
After all this is done, remove the battery to a safe place, but not on a concrete floor. Check it periodically through the winter and re-charge as necessary.
This sounds like a lot of work but much of it will be work you don’t have to do during spring commissioning, a time when you want to get back on the water as soon as possible.