1962 mercury outboard (500)50hp4cyl 2stroke . Ijust replaced the impellar & water pump gaskets . my question is there's a copper tube that comes off the waterpump & goes up into the bottom of the power head . ican't physicaly see where this tube connects. there is aplate below the powerhead that wraps around the outside of the center section , but i can't get to anything from there . any idea how i can reconnect the tube , iimagine it is what sends water up into the power head and cools the top end . (my manual doesn't show or evnen say anything about this tube .