I have a 2001 C40 hp 2-stroke yamaha that seems to be overheating. Sometimes the overheat alarm goes off and sometimes it doesn't. The tell-tale hole is peeing strong and I have already replaced the impeller. I have also replaced the thermostat and tested to make sure it is working (dropping it in hot water). The water coming out of the tell-tale is 140 degrees. Which seems too hot to me, but I am not sure what temperature it is supposed to be. I have also run the motor without the thermostat and it does the same thing. Any suggestions would be appreciated.