I've replaced the radiator, water pump, thermostat. All needed replacement but still have the problem. I noticed today that the electric fan is not engaging when I turn on my AC. I haven't run it hot enough to see if it comes on with elevated engine temp. I may wire it to a switch in the cabin so I can have it on when I want it.

 

If the fan motor is bad, a switch will not solve the problem. With the engine running, unplug the connector at the t-stat cover.....if the fan motor, relays, fuses and sensor in the stat cover are good, fan should come on. If not, start chasing electrical from/between the sensor all the way to the fan.