I picked up a 20ft thompson with an i/o in it. it has a ford engine. i have never owned an i/o. can i use regular auto antifreeze to winterize it? I got it at an auction, and it doesn't have an owner's manual. guess i will have to teach myself.
take it to a marina and pay the $100 if you can afford it. if not you have to remove the drain plugs in the manifolds and use the 100 degree blue antifreeze