Now that you have all the tools required it's time to begin the process. Follow steps 1 through 3 (flush and drain) of the two-stroke process and proceed to step 4.
Step 4:
This step includes the draining and changing of the engine oil on your respected four-stroke. To do this, you are going to need to locate the drain plug for the engine oil. This will be located somewhere on the side or leg casing of the motor. With the cowling off the motor, remove the drain plug from the leg casing and drain into an oil pan or bucket that can be used to properly dispose of the old oil. After the oil is drained, put the drain screw back in the leg casing and find the re-fill location in the user manual. Once located, add the proper amount and specific grade of OEM oil. When re-filling, always use a funnel to avoid any spillage or mess.
Step 5:
Changing the oil filter. Like a vehicle, this is a rather easy task to complete. Completing the task will require the proper sized filter wrench or strap wrench to remove the old oil filter. When installing a new oil filter be sure to seat the outside O-ring. To do this with a finger, simply rub a small amount of engine oil on the outside O-ring. When replacing, hand tighten the new filter and then snug it tight using the correct size filter wrench or strap wrench; do not over-torque the filter.
After the oil filter is securely in place, refer and complete steps 4 and 5 of the two-stroke winterization process. You are now ready for the final step of the four-stroke process. Same as its counterpart, the two-stroke, it is highly recommended to change the lower end oil or gear lube. An identical process for four-strokes - except for the location of the drain plug on the lower end. Some four-stroke motors require removal of the prop to access the drain plug. To remove the prop, use a piece of wood to prevent damage and movement of the propeller. With the wood preventing movement, use a prop wrench to remove the nut and pull the propeller off the lower end. After the lower end drain plug has been located, drain and re-fill using the same process used in step 6 of the two-stroke.
These winterizing tips are the basic do it yourself tips. Changing your fuel filter, grease fittings, and changing bearings on your trailer are some other tips that I would suggest you complete each year. Although doing it yourself is a great cost saver, I do highly recommend a trip to a boat dealer for service every one to three years depending on the amount you use your watercraft. Impellers, drive belts, compression on cylinders and having seals checked are all good preventative maintenance that I personally like to leave to the dealership.
New oil filter
Specific grade of OEM oil for your outboard Piece of wood
Correct size filter wrench or strap
A Funnel
Prop wrench or proper size socket (not required for all four-strokes)
First, make sure that you have all the appropriate tools involved with storing your four-stroke. Along with all the same tools needed to store a two-stroke engine, you will also require: