Yamaha F60 CET overheating

Anybody know what is wrong with the engine?after 10 15 min when I gas up the alarm sounds, indicating that the overheated, oil gasoline and water cooling works fine so,I stop the engine for a few minutes and start it again,do not know what is wrong with engine.

Could it be that there is something wrong with the cdi box,or clogged water cooling system,or faulty temperature sensor?We've had the engine a little over two years and had not changed spark plugs yet but oil and filter them we change.

Need to help
I have changed a new thermostat and a new impeller and the change new oil and filter nothing helps...

aada, when you replaced the impeller did you twist it in the proper direction so the bend of the fins matched the bed of what you removed? When you replaced the thermostat, did you put it in same as the one you took out and didn't put the new one in upside down?

Hook the engine up to "ear muffs" and see if there is plenty of water coming from the pee-hole and the exhaust from the center of the propeller. Maybe take the cowling off the ourboard, pull out the thermostat and then have someone start the engine for a few seconds and see if plenty of water makes it's way all the way up there. IF it does, I think you're engine is probably fine and you may need a new water temperature sensor. Sensors go bad all the time but engines are simple. If the water is flowing fast and not steaming hot it is probably a sensor.

Thanks for the reply
Now it's not the first time I've changed impeller and thermostat ... it's just a little different with 4 stroke engines a 2 strokes but one is that water cooling is hot but not so hot.I'm doing an experiment with the thermostat and see what happens..

I had heard that a small piece of zinc anode should be cause the engine to overheat,it also showed that the small piece of zinc anode is broken off and fell into the cooling system and blocks explain part of the cooling system,that I have removed and tested the engine in half an hour,and there was not no alarm,I hope that it is the cause of the engine overheating..