changed thermostat, temp switch and still over heating altho needle stays half way ? water bubbling away like mad in expansion tank ! and releasing steam and water under pressure. Top and bottom hoses are hot but the rad is cold ! got hot air blowing inside the car fine tho .

what i want to know is , would i get hot air blowing (nice and hot) inside the car if the pump was gone ? and secondly how to bleed the system correctly?
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