My overheat alarm goes off sporadically on my '92 Merc. 100<br />There seems to be no rhyme or reason to when it goes off. This is the whistle alarm.<br />Sometimes it goes off while running hard for a bit, other times it will go off while idling. Even did it on a cool start (not cold).<br />It rarely goes off for more than 20 or 30 seconds, if that long. At times, it also sounds "weak", like its just barely trying to whistle.<br />A buddy says he thinks its the impellar, it was replaced two years ago, and doesn't have 10 hours on it.<br />Any ideas?<br />Ken
