I do not understand that you mean the direct fan, if it is electric, it is not good that it is working all the time, if it is viscous coupling, it does not work well the clutch of this and "it lacks revolutions" despite the fact that you see it turn ... to purge the circuit, you must open the passage of the habitaculus (put the maximum heat position Purgadores, you can disconnect the output sleeves from the butts until water comes out, after connecting these, you assure you that you fill the radiator as you have said. You start the engine with the filling plug removed so that the air is coming out, when it starts to heat, you cover it and wait for the fan to start working, checking that the input and exit hoses are already hot (opening of the thermostat) and it is when you have to add more water (care when loosening the plug ..) you stop it, and when it is cold, add up to it.