I HAVE A 2005 mcs, THAT WAS MODIFIED BY "DIANA" STAGE 5. I LIVE IN SAN ANTONIO TEXAS. DURING THE SUMMER MONTHS( ALMOST ALL YEAR) THE TEMPERATURE RANGES BETWEEN 100-110 DEGREES. I RECENTLY INSTALLED A WATER TEMP. GAUGE, TEMP. RANGES 210-230 DEGREES. i HAVE BEEN LOOSING COOLANT. REPLACED THE HOLDING TANK, CHECKED THE ENGINE FOR SIGNS OF OTHER LEAKS, NOTHING. THE RADIATOR FAN HAS BEEN CHECKED, BOTH HIGH AND LOW SPEED AND SEEMS TO BE WORKING OK. MY QUESTION IS DOES ANYONE THINK I AM BOILING-OFF COOLANT WHILE I AM DRIVING???
AND DOES ANYONE HAVE ANY EXPERIENCE WITH REPLACING THE RADIATOR WITH A "MISHIMOTO" RADIATOR???? IF SO DID IT HAVE ENOUGH CAPACITY TO LOWER THE TEMPERATURE ENOUGH TO PREVENT LOOSING COOLANT??
ANY ONE IN THE SOUTH WEST US EXPERIENCING SIMILAR PROBLEMS???

 

Wow....all caps...
screaming...hurts my eyes...
coolant does not boil off unless you have a leak or are ovrheating and venting through the tank top...
Sounds like you have a slow leak somewhere....thermostat? Maybe around where the radiator crimps to the plastic side tubes? Look around...

 

You may have to dig around the engine with a flashlight, but look for tell-tale signs of the leak as Zippy mentioned. Most common is around the thermostat. Other places can be under the fluid reservoir, where the pipes connect to the radiator and engine block, and the radiator itself.

For boil over, look at the cap area of the fluid reservoir. If you have a white film around it, you've got escaping fluid (cap not on tight if it's not popped up).

Temp range is normal so you shouldn't be boiling at all unless you have an improper coolant (such as 100% water -- which would also invalidate half the tests looking for leaks).

For the Mishimoto radiator, they make one specifically for the Mini so it will have appropriate capacities. From what I've read it will lower your coolant temperatures in turn lowering the core temperatures.

 

iT CoULd InFinItEly BE wOrSe. smeotihng lkie tihs for examlpe is awlays wrsoe in my oipnoin. The text could have been in colors too. WnOeDR wAhT tAhT WUoLd LoOk LkIe If AlL pUt TgOeHtEr? Oh. That.

On a serious note, from what I understand the thermostat on R53s are something you need to keep an eye on. In other words, listen to Zippy and proximo before you go spending a bunch of money on something that may not be the problem.

 

If you are indeed, losing anti-freeze, it's going somewhere. Either it's leaking from your cooling system or going into the engine through a bad gasket (intake or head). I agree with the advice given above, don't use a shotgun approach to find a pin hole---find the problem, THEN decide what the appropriate action is to properly fix it!

 

I installed a Mishimoto radiator in my 04 MCS.
For two months it worked great untill it sprung a leak where the core meets the right tank.
Poured in a bottle of liqued Aluma-Seal until I can get a replacement.

Jim

 

Jimz68- Did you get the replacement from Mishimoto?

 

I think i am blind now.

 

That expansion tank is subject to embrittlement. Depending on mileage, consider replacing it regardless. Mine was toast at 70k miles and leaking out of top cap, but then again, that was on the race track...

 

which tank? stock or Forge?

 

Stock tank.

 

Anybody using a Forge aluminum unit or mishimoto radiators?

 

You should replace your 195 thermostat with a 180, (i bought a Motorad and its been working great) Im In SO CAL / san diego , I also have an after market Coolant guage along with a toogle that grounds the stage 2 relay and turn on the high speed fan when I want , which is usually anytime its over 100c. Heat is an engines enemy and the 112c stage 2 is just too hot, I have a billet expansion and silicon hoses and i dont lose a drop any more.(always use BLUE coolant) I was having hot running issues and the car exhibiting some strange effects of it (fan on after engine off, Stalls and starts, an electrical surge once....) after reworking the cooling system now i have a very PREDICTABLE performance and reliable running system that performs very well..... the 180 degree themostat was a big part of it for my circumstances....... SOme may say youll throw a code with a 180 but ive been 2 + months with not a DTC to be seen. 105 C for stage 1 fan is just not a healthy temp to run at , it cooks the gaskets and seals I KEEP IT in the 90's up to 101 at the most, freeway speeds it cools to the high 80s in 90 degree weather..... ALL JUST MY EXPEREINCE IN MY 2006 MCS with 85K.... Any thing i can do to help just reach out