Winterizing a 4 stroke

Looking for info on how to winterize a 4 stroke (2 motors a 90 & 40 oldest is a 07) trying to cut costs this year and do it myself.

Thanks

I have winterized my F150 since 07 by following the manual – never had an issue.

-ted

I have a 115 Merc 4-stroke, always done it myself, no problems. I run seafoam in the gasoline and spray the cylinders down with a fogging oil when I put it up. 2002, 7 years and still running great!@

Change oil/filter and lower unit oil.Fill the gas tank,add Stabil or SeaFoam. With engine running(hose attachment on motor) a few minutes, fog it about 15 seconds at the air intake and shut it off.Drain water from the that water flush hose on the side of motor(Yamaha).

I don’t fog 4 strokes, especially if EFI. You can remove the spark plugs and spray a little oil into each cylendar instead.

Tip – get the hand pump for the lower unit oil. Makes the job a breeze! Like the one shown here

I’d also hit all of the greese zirks with a shot of fresh greese. Remove the prop and inspect for any tangled line in the prop shaft.

-J.

Pool 4 stays open all year don’t winterize just use it every 2 weeks.

I Seafoam the gas. Make sure its running through the motor then disconnect gas line and run it out. I fog the intake (disconnect spark and turn over engine) but usually not the plug holes because its difficult getting plugs out. Normally I would hit them too. Drain and refill lower unit. Good to go. That is what I have always done and will continue to do so. I empty remaining boat gas from can into my truck. With internal tank I would just leave for next season since it is treated. Some people top them off before storage but I have always topped it off with fresh just before I run it the next spring.