i have a 1981 140hp evinrude,the last time i took it out the lake had alot of junk floating around from all the rain so im guessing i sucked something up into my motor cause now the tell tale is very weak,and if i full throttle my motor the buzzer starts going off,everything in the cooling system has been replaced so what do i need to do to get the garbage out of there so i can use my boat again,thanks