2003 Johnson 150 overheating

[hv2hunt]

I just purchased a pontoon this summer with the Johnson 150 (2stroke) on it. So far I have had to replace the stator, the flywheel and I replaced the water pump. The plugs have been replaced, the thermostats have been replaced and the primer bulb, then I noticed the carbs leaking in the throttle body's, so I rebuilt 3 of the 6. It has all been running good until fired it u after the carb stuff, the moor ran fine but the water temp light came on and even now after a couple days. a turn the key on an the water temp is still going off. I have put the temperature gun on the head and it doesn't seem to be running hot. About 150 to 170 range depending where you point it. Why wont the alarm go off???????????

[Rebel Sympathy]

Possibly you have a bad temp sending unit in the head. Two tan wires: One to alarm; the other to S.L.O.W. circuit in power pack. Disconnect lead to horn. See if horn stops. If both heads have sending units, try each seperately. If so, replace bad temp sending unit in head.