Two stroke or four stroke?? Two stroke needs lower unit drained and replaced with recommended type fluid. Fuel needs to be STABILIZED and then run motor dry of fuel. Service fuel filters as recommended by manufacturer. While running motor dry, use a quality fogging oil and follow instructions on container. Store motor in down position which will allow complete draining of water. Check battery or batteries for water level. If low use distilled water only. Charge battery completely before storing. I NEVER remove from my boat. If battery or batteries go bad over the winter, replace them. Check prop for nicks, now is the time to get it repaired.
If a four stroke, do all of the above plus also drain and replace crankcase oil with quality type and replace filter.
In the spring, replace spark plugs after starting motor and burning off fogging oil.
Hope that helps. Call me and I'll be glad to assist you further.
