4-tec...
We have a thread dedicated in the forum for winterizing, but for the most part, covers the two strokes.
Since the 4-TEC is a 4 stroke engine, with it's closed loop cooling system using a 50/50 mix of anti-freeze, I'd check it with a hydrometer to make sure it was still capable of handling freezing temps. It has valves that keep the pistons proteced from the outside elements (humidity) and an oil sump that protects the crankshaft. So, outside of washing the exhaust, making sure it is water free, by starting for a few seconds, I don't think there is a lot you need to do for it.
Maybe spray the linkages down with a water displacing lubricant.
This engine is in principle, the same type engine in your car. So, what ever you do for your car, you can do for the ski.
There are operators manuals and 4-TEC manuals in the library that cover winterizing.............give them a look. The procedures are located in the front of the books.................:cheers: