Our Mini cooper 2002

[SteveLakin]

Dear Al

Hope you can help. We have a 2002 Mini Cooper which runs brilliantly, it just has a starting problem. The car starts straight away, but a minute later the fan goes on and the temperature gage goes to the top. We turn off and restart the car and sometimes this works but recently the fan and temp goes up again, or it sounds like it is flooded. We come back to the car 1/2 later and then it seems to start no problem, and the temp stays normal. Its been serviced, and all levels are correct. Its only done 54k miles, so its a great car apart from this problem. Please help. Thanks.

[mike9009]

Dodgy thermostat??

[Shedding]

Dodgy thermostat does seem a good candidate.
I also have a 2002 Mini Cooper and once warm, the temperature gauge sits right in the middle of the dial or if a very cold day, just slightly below. Is this where yours sits normally?

[R53rider]

If it is doing that cold it won't have anything to do with the thermstat. It is mechanical, it opens by heating up wax inside it (yup, that archaic, but it works so they've never changed it) opens at about 88C depending what temp stat is fitted.
The standard gauge is pretty useless – a very rough indication only. It is only accurate +/-20°C, so it will stay on the middle mark from 70°C to 115°C. I've measured it with my Ultragauge.
Car should run at about 88ºC-90 ºC. Car moving, open road, should stay around here.
Low Speed Fan (if it is triggering) should cut in at 105ºC (but it is quiet, hard to hear)
High Speed when the coolant reaches 112ºC (the small jet taking off sound)
I reckon it is your temp sender that is knackered. But I may be wrong!!