Hey all - I'm new here!

Bought a 2005 Cooper S last month (5,100 miles from new) and finally joined the Mini fam.

I've been noticing a sporadic/non-consistent issue with my coolant level. Every now and again, there will be coolant leaking from somewhere under my car - it's not every single day, either. I took it to a local garage and had them pressure-test the system, but to no avail. They ran it for 2 hours straight and were unable to replicate the problem. My thoughts are that it could be either a loose connection somewhere (seal has worn out).. or that there's an overflow hole where excess coolant will drain from. My mother's Crossfire has that kind of deal with the windshield washer fluid tank - you can't see where the "full" line is, but once it reaches maximum capacity, it will overflow onto the ground.

Have any of you had a similar issue or can possibly explain why she's doing what she's doing? I appreciate it!

 

Have you checked the common leak spots? Thermostat housing, overflow tank seams? I believe there are others.

 

Bet $100 you have the original EARLY thermostat with the faulty gasket material....
A revised one came out....and with so few miles on that car (5100?!!) Lots of items that were fixed under warrenty will be done on your $$.
An S does not have an overflow ....the tank is preasureized...if overfilled, it will squirt out the cap which doubles as the pressure relief devise...and often the early seem clear tank (changed to a yellowish one...improved) will split and leak along the seam....

 

I had the same issue. Coolant leaked when the engine was cold. My diagnosis was the t-stat gasket and my trusty independent garage confirmed it. The gasket was replaced with the new and improved version along with the housing, thermostat and a coolant flush. Might as well get it all while it was opened up. Total bill was $280. It is recommended to fill the coolant tank to below the seam or just above the baffels to prevent a tank failure at the seam. Good luck.