oil is oil for the most part, but the viscosity, or thickness, would vary depending on the ambient temperature it is designed to work at. Outboard motor oil would be a higher viscosity (thicker) since it is for summertime use. It most likely would be too thick in cold temps for your oil pump to move it. That's why automobile motor oil is multi-viscosity 5w30 etc. It flows like a 5 weight when cold, but holds up its thickness like 30 weight when the engine warms up to operating temperature. I would NOT recommend using outboard motor oil in a snowmobile, you will most likely have problems associated with poor lubrication.