I didn't know that the 4-stroke seadoo's are cooled using a radiator. I seen the poll asking what do you use to cool your 4-tec and i was thinking duh lake water??? But then i read up on how they use a closed loop system and how the coolant is cooled down using a modified ride plate. Hmm, forgive me im a 2-stroke kinda guy still. Did they always have it this way from the start of the 4-tec's?