I've just inherited a 2005 Cooper Convertible project with 149K miles and need some advice. A short time ago it developed a coolant leak which quickly got serious. Unfortunately I can't see where it is leaking from (it drips off the oil pan from just below the AC compressor), despite having taken off the bumper, bumper extension and wheel well liner (Kudos for the compact packaging). In addition to the visible leak, which only starts after the engine reaches operating temperature and stops when the engine is switched off, there is a second leak. About 5 to 10 minutes after shutting the motor down, there is a gurgling sound and the coolant level in the reservoir goes from 'Max' to 'Min', but no more coolant goes to ground. I suspect the head gasket and am prepared to strip it down for replacement, but was wondering if it might be something else. Has anyone had this experience?

 

Look at the thermostathousing for the leak that doesn'tdrip...
The radiator, or possibly the waterpump should be looked at...
The waterpump has a "weep" hole that allows coolant out when the seals fail internally.

The radiator itself can have the plastic end tanks crack where they are heat set to the metal tubes....common fault with this type of unit, and all modern units of similar construction.
I would look closely before yanking the head....

 

Thanks, Zippy; I've cleaned up for this weekend so will have another look next weekend and let you know what I see.

 

The radiator may also need a flushing. Here is some background info and articles that may help! Please let us know if we can help!

http://new.minimania.com/MINI_Routin..._I_and_II_2344

http://new.minimania.com/Cooling_Sys...R50_52_53_MINI

Drive Hard. Drive Safe. Keep Grinning.