Ok I put my center console on the water for the first time since owning it for 7 years , it has been a long rebuild process on the hull but it finally hit the water. The engine is a 1990 Johnson 125 ( J125ESXESS ) the issue is after idling for 4 or 5 minutes the overheat alarm was sounding , I used a temp gun and I was getting 130-148 around the thermostat housings and the outside of the engine cylinders were 150 degrees. Is this warm enough to set the alarm off ?
This motor originally used a water control valve that has been since discontinued , so I bypassed the valve and did the thermostat upgrade from a 1989 70 HP ( 140 degree temp stats ) with the springs and gaskets that I learned from this site , the thermostats are now a couple of years old as well as the water pump but they don't have 2 hours of run time on them.
I believe the temp sensor in the head on the port side of the engine ( 2 wires ) is bad because when the alarm sounded , I unplugged the starboard sensor and the alarm kept sounding but when I unplugged the port sensor it quit , is there another way to test the sensor , they are still available but are very expensive so I would like to be sure before I throw parts at it ! Any help is greatly appreciated.
This motor originally used a water control valve that has been since discontinued , so I bypassed the valve and did the thermostat upgrade from a 1989 70 HP ( 140 degree temp stats ) with the springs and gaskets that I learned from this site , the thermostats are now a couple of years old as well as the water pump but they don't have 2 hours of run time on them.
I believe the temp sensor in the head on the port side of the engine ( 2 wires ) is bad because when the alarm sounded , I unplugged the starboard sensor and the alarm kept sounding but when I unplugged the port sensor it quit , is there another way to test the sensor , they are still available but are very expensive so I would like to be sure before I throw parts at it ! Any help is greatly appreciated.
