1984 140 Johnson

My dad has not ran his boat in 3 years, it has been kept in a garage out of the elements. It had fogging oil put into the cylinders after he last put it up, and has been added two the last two years. I hooked a new battery up to it and the starter would barely turn the flywheel. The battery is new and the starter looks good. There is a grinding/rubbing sound coming from the lower unit when I turn the flywheel by hand. I’m thinking it could be the impeller is not allowing the flywheel to turn fast enough. Any ideas?

Rubber impeller for water pump. The scrapping sound you hear could be rings on dry rusted cylinder walls. Even though you used fogging oil. Take plugs out, tilt engine up high as you can and rotate where 2 cylinders are pointed up. Spray a bit of penetrating oil in each cylinder and slowly rotate with socket and ratchet a couple of times while spraying in a little more oil. Let sit over night then do other side let sit. Them tilt back down rotate a few times then spin over with starter. Not much just enough to make sure it’s free. Remember your crank and bearing are probably pretty dry because of no oil for a long time.

As Cray said. Now transmission fluid seems to work better imho. Just don't leave atf in cylinders more than 24 hrs.