My 2009 STX is overheating and the fan clutch will kick on when it gets hot. I've had problems in the past with thermostats. I removed the thermostat and the engine is still getting hot. I don't know if I'm overlooking something or what, but if the fan clutch is working and the thermostat is removed it should not be overheating.

 

Sure it can. If the water pump isn't pumping. Or you have an air bubble in the system. Also, I would put the thermostat back in. It allows the engine to heat up properly without wasting fuel. Thermostats are basic in their design. It is not a high failure part.