overheat alarm

[ara23]

I have a 75 hp honda. When i run it at WOT after 3-4 minutes I get a High Temp alarm and the motor losses rpm's, after letting it idle for 5-7 seconds the high temp alarm goes back to normal and the motor will run fine. if I run the motor at less than 5000 RPM's it will run fine all day. I have changed the water pump, and thermostat. I have a water pressure guage installed and it reads 25-27 psi at 5000 rpm's. any ideas? is there a way to check the sensor or would it just fail and not work at all.

 

[bgtruk21]

Re: overheat alarm

any luck figuring this out?
I just bought a boat and the guy told me to keep it at 3800 rpms. its a 75 hp honda, well being the first time out I tried to do that but the same thing, about 3/4 throttle for maybe just under 10 min. the engine went to idle and the alarm sounded untill I dropped the control to idle, if I put it back into gear it was okay, but anything over 1000 or so rpms the alarm would go off again.
I never shut the engine off and maybe after sitting for 30 seconds it would be fine for another 5 min.

when I got home I checked the oil and it has a steady pee.
would like to know if you figured it out, these 4 strokes are new to me.

thanks for any help