How To Winterize A 2 Stroke Outboard Engine

If you are a proud two-stroke outboard owner and ever wondered how to winterize your engine for the off season, here's your chance to learn how to do it. We will give you a step by step approach on how to do it and a list of everything you'll need to get the job done right and save yourself a lot of money at the end of the day. I have based this off of a 2 stroke 150 Yamaha Outboard Motor but the same principals apply to all 2 strokes.

List of Supplies:

– Earmuffs

– Hose

– Screwdriver

– Stabil fuel stabilizer

– Socket Wrench

– Fogging Oil

– Lower Unit Gear Oil 1 Quart

– Pump to fill lower unit

– Washers to place on the lower unit screws

Now that we have all of our supplies which will cost you approx $ 30 as opposed to 300 to have your local mechanic or marina do it for you, we're ready to begin.

First things first unscrew your gas cap and add the appropriate amount of stabilize into your gas tank, just follow the directions on the container. Then remove your engine cowling and unscrew the cover over the carbs if you have one (mine has 12 screws). After you have done that hop off the boat and place the earmuffs on the intake screen on the lower unit and make sure the water is flowing out nicely before you turn the engine on.

After you have made sure you have a good stream of water turn the engine on and run it for 15 minutes flushing out any temporary salt that may be in your engine. Do not be alarmed if the engine sounds louder because it will since the muffler is usually under the water and you will see some smoke coming out of the prop that's exhaust fumes. MAKE SURE you see a nice stream of water coming out of the "pee hole" it wont be as strong as when the boats in the water but it should be steady.

Now that we have ran the motor for 15 minutes its time to start fogging the engine. With the engine still running start spraying the fogging oil into each carb alternating evenly among them. Continue doing this till the engine almost stalls on larger motors, you will hear it begin to conk out and smoke excessively. If that happens then you know you're doing it right. After you have done this and the engine almost stalls out, shut the engine off. ** Note: on smaller outboards the engine will stall that's fine. **

Next we are going to fog each spark plug. This is where your socket wrench comes in handy, unscrew your spark plugs and spray some fogging oil into each hole and on each plug and spin the flywheel to work the fogging oil in after you have screwed the plug back in. Do that for each plug. When that's done its time to take care of the lower unit oil.

Moving on to the lower unit gear oil, here's where it can get a little messy. Make sure to place a drain pan underneath the unit before you begin to take any screws out. Now there will be 2 screws you will need to unscrew in order to drain the oil. The first will be found near the bottom of the skeg, you unscrew this one first and oil will begin to immediately pour out. After you have taken that screw out you can unscrew the second screw which will be found above the first screw above where the earmuffs were you cant miss it. Once you finish unscrewing that the oil will drain much faster. Allow all the oil to completely drain out before adding the new gear oil.

In the meantime you can take the old washers off the screws and put the new washers on while waiting for all of the oil to drain out of the lower unit. As its draining inspect the oil to make sure that it is not milky meaning water is getting in there because then you will have a bigger problem on your hands. Alright, now all the oil has drained out its time to fill up the lower unit with new gear oil. You take the pump you bought (each manufacturer makes their own just ask your local marine store) screw the pump into the bottle and place the other end in the skeg drain hole. Begin to pump and keep pumping until the entire quart is gone and screw the skeg screw in first because oil will quickly begin to come back out. Then after that screw is in you screw the second screw in and guess what YOUR DONE!

That was not so hard now was it? Just clean everything up, screw your carb cover back on and place the engine cowling back on and shes good to go for the winter. If you have any questions please do not hesitate to ask me, I would be more than happy to.