Even after working the machine for hours the temperature gauge barely moves off C. I have replaced the thermostat. Upper hose hot when running so the engine is heating up. When I remove the lead to the temperature sensor and short it to the frame the temperature gauge moves to H. I have read other posts suggesting there is a calibration issue wherein the temperature read by the sensor is not being accurately displayed by the gauge. I don't really want to purchase a new sensor if this will not fix the problem. Any advice/ similar experience is appreciated.