Radiator fan kicks in too late
Hi. I have a 2004 R50 Cooper.
I have a problem with the coolant temperature, when I use the car it always looses some coolant level.
I changed the thermostat, the thermostat housing, the coolant cap and the coolant temperature sensor (the one on the block of the engine), I tested the cooling fan and it works fine on both stages.
I checked the oil and the coolant and they are OK, the car hasn´t lost any power at all.
The problem is that the radiator fan kicks in too late. I did a test on my garage, I put the car on test mode showing the temperature on the instrument cluster.
The temperarure started to raise normally, at certain point I started to acelerate the engine and the temperature started to raise, the problem is that when the coolant reached almost 100ēC, the coolant level on the reservoir started to raise almost getting to the cap, then the radiator fan started to run until the temperature reached 105ēC.
When the radiator fan kicks in everything started to become normal, I repeated the test and the same happened.
When I use the car with the A/C on it never looses coolant (because the radiator fan is always running), so I think the water pump is OK.
What can I do? Is there another coolant temperature sensor? Is there an adjustment of the temperature point for the fan?