Over heating Alarm

[uneakfshrmn]

I have a 1999 70hp Evinrude outboard and the S.L.O.W. warning buzzer sounds after it runs for a little while. Thermostat is good and plenty of water going thru the motor. The sensor was replaced not long ago. Any suggestions

 

[Boobie]

When's the last time the water pump was serviced ??

 

[uneakfshrmn]

When's the last time the water pump was serviced ??

Last fall before I stopped using it. If I let it run the alarm stops but red light stays on. Water comes out the back and is cold, I took the thermostat out and put it in a bowl and as water got warmer it began to open so I now it works.

 

[Boobie]

If you have System Check, you could have a bad tach. OMC had some bad ones.

 

[Scod]

Last fall before I stopped using it. If I let it run the alarm stops but red light stays on. Water comes out the back and is cold, I took the thermostat out and put it in a bowl and as water got warmer it began to open so I now it works.

Disagree. I also have an overheating issue. Narrowed it down to my port side thermostat. Put both thermostats in a pot of water and even though they both opened the bad one opened at a higher temperature. Don't assume it's good just because it opens, check what temperature it opens at.