I have a coolant leak at the joint between the thermostat housing and the crossover water pipe. It isn't that bad but I have to drive 30 miles for an emergency before I can fix it.

Any advice or caveats? The car is a 2009 Cooper S hatchback R56 - N14.

I intend to fill the reservoir up to the Max line before leaving and have live data on my 'Carly' displaying motor temperature. (why the hell don't they have better naming of the live data sources on the Carly App?) I have never seen it climb above 221 degrees. I do not want to blow my head gasket or overheat the car at all. What temperature should I pull over before waiting for the Overheat warning light to go on?

Sorry for the basic question, it's just that I plan on fixing it soon (this weekend) and can't wait that long before making that trip. I guess over-filling the reservoir is a bad idea too, eh?

Thanks.

 

It doesn't sound like a bad leak so you should be safe doing a 30 mile drive. It will only over heat if the coolant level gets really low. You will get a warning light 1st before a 2nd overheating light comes on. Carry extra coolant with you. Good luck.

 

Warning light being yellow and overheating light being red, correct? ... and thanks. I have only had this car for six months and it has been fine the whole time.

 

Don't 'fill' the expansion tank, it needs room to expand - half-way should be fine. I wouldn't rely on MINI gauges or lights as they are notoriously vague. Let the engine cool a little & check the tank at 10 & 20 miles.

 

I do have the Carly App so can monitor temperatures. Do you know what is a dangerous temperature to get above? I also realize that the temp will keep rising if I shut the car off.

 

230 or above should kick on the high speed fan, that would be the temp to try and stay under. I filled my overflow to the max line and drive 10 miles no overheating, did baby the car and drove posted speed limits, 9 miles of this were on the highway. Then did the same thing to drive to the mechanic 2 days later but he’s only 2 miles away.