What I normally do MF, is give it a light clean with spray on degreaser from sca or repco ($1 a can on special) and hose steering away from the engine.
Then once I have worked on it and have had it running, I will spray more liberally to clean it and hose (trying to avoid any cowl openings), then run for 15 minutes to dry out
My initial cleaning of my Victa 2 strokes is careful and effectively no water gets near the top of the engine - but thats because they are my favourites
