Re: Goodyear oil type
Depends. There were two kinds in 1951. Does it have a neutral clutch? If it does, it takes 80-90 weight outboard gear oil, available everywhere, including here at iboats. If it does not have a neutral clutch, it takes outboard gear grease, no longer made. Most people use Lubriplate #105 Motor Assembly Grease, available at NAPA Auto Parts stores.
Either one you put it in the drain plug till it comes out the vent plug. Both kinds of lube come in a squeeze tube. Or the oil type also comes in a bulk bottle, and iboats has a handy pump to put it in the motor.