my sisters 03 mini s is over heating.put a new thermostat,fan works,coolant flows through the rad fine when i put the garden hose to it..i bled the coolant but never got any flow at rad hose with engine running ..removed the intake to get at 02 pump but it looks fine to me.gear in rear of the SC looks good .no noise .slotted gear in pump and SC spin free[the gear at the SC spins when i crank engine]. nothing seems wrong..am i looking at a head gasket ? it over heats immediately and the expansion tank split in half while she was driving it.

 

I should have had the heat on full before i bled the the coolant,works like a charm now.

 

Could have a problem with the heater core. This is typically found behind the dashboard inside the car. It's responsible for circulating the coolant from the radiator to the area where your HVAC blower motor is located, thus enabling you to have "heat" in your car. My guess is that it's clogged, although it's a bit surprising given the age of the car.

 

indeed,this is very likely as its a miami car and may never have had its heat on.i had to bleed it several times,its possible that the hot coolant busted through some crud in the heater core which then allowed me to bleed the system properly.
thank you.