I have a 2004 90hp Johnson ,the hot alarm goes off while moving slow.I talked to a mechanic he said to put a new Thermostat in,I changed it and it ran fine for about 1 hour then the alarm started again.The water is flowing through the engine ,and it runs great as long as I am cruising .Could it just be a bad sensor?? I hate to take it to the shop for something trivial,but also do not want to blow the engine.Any knowledge on the subject it appreciated.
If it is going off while idling, I would suspect a water pump. You aren’t turning enough RPM’s to pump the proper amount of water through. When was the last time you changed it?
Thanks for the input.I went out Friday did not have any p[roblems ar all??