Winterizing Outboard Motor in the Water

winterizing outboard motor with Boat in the Water, then on the trailer for winter storage.
You do not need to take the spark plugs out of the Engine !
A cold crappy day means nobody is at the launch ramp. Great !
NOTE: The whole idea of doing stabilizer and fogging in the lake,
is to save time and the hassle of the Ear Muffs, and wet shoes.

Pour stabilizer into the gas tank
Remove air box cover
Spray fogging oil into the engine
Put air box cover back on
Drain lower unit lube
Fill lower unit with new lube
Check, fill, and charge battery

1. Pour the Stabilizer into the gas tank. After pouring stabilizer in the tank, mix the stabilzer by shaking the gas tank.

Start and run the engine for 10 to 20 minutes, or a last boat ride to the trailer works for me.

2. Remove air box cover. Pull the boat up on the trailer at the launch ramp. With the engine still in the water (for cooling). Shut off Engine and remove the Engine Hood. Then remove the air box cover on the front of the engine, exsposing the carburetors. Do not loose the screws or the plastic cover in the lake.


engine in the water take hood off	remove air box cover screws	take air box cover off

If your engine has a direct hook up for the fogging oil, you do not need to pull the air box cover off. Hook up the can to the fitting on the engine to inject the oil.
Don't have a fitting, or can't find it? Just take the air box cover off and follow along.

Special Note for 4 Stroke engines do not have an Air-Box-Cover. They have an Air-Horn or plastic air intake that you spray the fog oil into.


yamaha 25hp 4 stroke engine	find the carburetor on the side	look for the air intake horn

keep clear of the flywheel
while engine is running

3. Spray fogging oil into the engine. Start the engine and spray fogging oil into all the carburetors. Just spray a little in each carb, and keep sraying in each carb with longer blasts, untill the smoke is rolling. A big blast in each carb should stall the engine for you, or shut it off with the key as soon as you stop the spraying. Remember to turn off the key after you stall it out on fog oil.

Use almost 1/4 can for small engines, 1/2 can for v-4, and 3/4 can for v-6 engines.
Fogging Oil is a wax-base oil that prevents rust from forming on metal parts inside the engine. Don't worry about getting it all over the place, no problem, it will only prevent rust.


with engine in water. start engine	spray fogging oil into each carb, untill the smoke is rolling	then spray a big blast in each carb, to kill the engine

4. Put the air box cover back on. Pull the boat off the ramp.
Put air box cover back on the carbs. Put the engine hood back on.

The water will drain out of the engine while
you put the air box cover on.

Take the drain plug out of the boat and head for home.

Now the Top part of the Engine is ready for spring time.

5. Drain the lower unit lube. Do this by removing the bottom drain screw. Put your container under the lower unit to catch the oil. Then remove the top vent screw to allow the oil to drain. (you will get a quart or less)

The drain screw is is in the bottom of the lower unit towards the front. The vent screw is just above the first fin on the side of the lower unit.
Sometimes the Vent and Drain screws are very tight. Use a LARGE screw driver and lean into it while applying twist, to get them out. Wipe the screws clean with the rag, some have little magnets on them. The screws will have a little gasket or 'o' ring seal, just reuse them.


place container under engine. remove drain screw.	remove vent screw. let oil drain out.	wipe off the screws.

Please do not leave the lower unit empty during the winter.
Rust can form inside on the bearings and gears.

6. Fill lower unit with new lube. Attach the hose from the pump to the "drain" hole and pump the oil in until the oil comes out the top vent. Put the top vent screw back in. Then take the hose off the bottom and put the drain plug in as soon as possible. A little oil will escape while you fumble with the drain plug. it's ok, no problem

If you are useing Tubes instead of a pump. Just snip the top of the tube open. Force the tip into the drain hole, and squeeze it in. Yes it is a little messy. Just force the lube in, till it comes out the top vent. Put the top vent screw back in. Then put the bottom drain plug back in as soon as possible. A little oil will escape while you fumble with the drain plug. no problem

Put the Vent and Drain screws in tight, but don't get animal with them, you have to get them back out next year !


hook up the pump. pump the Lube in.	oil running out the vent. it's full.	put vent screw in first,disconect pump and put drain screw in.

7. Check, fill, and charge battery. You should check the cells and fill them with water if they are low. (full is to the ring inside the cell or 3/4" from the top) Wash your hands when done to remove any traces of battery acid.


wipe off battery. pry the caps off with a screw driver	cells on left are full. add water to cells on right. put the caps back on.	hook up battery charger. red on Pos. terminal black on Neg. terminal

If you have a 4 stroke outboard, you should change your oil and filter.

You are basically done, all this in little more than an hour, for very little money.

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