i just bought a new to me merc 200 efi 2002 model,got it all rigged on the boat cranked right up and no water coming from tel tale,gave it a min still no water and alarm went off,shut it down and am trying to figure out what the problem is.The thermostas and gaskets are new,water pump was changed by a mercury dealer a month ago and was run by previous owner with no problems. Im a little mind boggled as to what could be going on and what direction i should go from here. oh and the engine was at idle on ear muffs