We have a 2019 Nautique 200 with the 6.0 liter engine and are getting engine cooling temp codes DTC 116, 1415 and 1416.
My wide thinks it humorous that we can't fix this problem considering the hours we have spent on it so far:
We have replaced the impeller and pump, reverse flushed the strainer, trans cooler and oil cooler, and tested and replaced the thermostat. The engine temp runs up to 200+ during a pass but cools at the end of the lake, so we know the thermostat is opening. The boat runs cold when no thermostat is in place but will not produce adequate power in this mode. The engine maintains temp when running city water into the inlet (essentially forcing more water through the engine).
Has anyone seen a similar problem?