Alright guys. I have a 03 MBS "R53", 85,000 miles. I had the classic overheating idle issue that goes away once you start moving again. I fixed this issue three weeks ago by doing a fluid flush and replacing all the coolant in the system. Topped it off twice since then (the last time being this past saturday). Car works and drives great, normal temp at idle and all. Yesterday (Monday) I was driving between 55 and 75 for about 45 min on the way to the airport. On the way down I hit a fairly sizable pothole (the road is littered with them) but this one jolted me pretty good.

Another 25 min of 75 mph speeds passed and as I got off the highway I immediately noticed my temp gauge going up before I even came to a complete stop to idle. At this point I knew this was different than the issue I had in the past. I pulled away from the intersection and did about 45mph to the nearest spot where I could pull over (the gauge stayed at roughly 7/8 of the way up to the red light). I pulled over and looked under the car (as best as I could) and could see that coolant had definitely been coming out of somewhere, it was all over the bottom and had clearly been spraying/ dripping back as droplets had reached almost the middle of the car, reservoir is totally empty. Called for a tow, had it taken to my buddies shop.

Today: My buddy and I started to try and identify what caused the leak. We put coolant in, ran the car for a minute and it started to leak a little from the underside of the intercooler. We removed the intercooler but could not identify where exactly it was leaking from. Could it be a hose? Tstat housing? I just figured I'd tell my story and see if anybody has any insights or similar issues. Thanks in advance for any advice given!
-Erik

 

I haven't hit any potholes, but I am having the same problem with idle overheat, my problem was a leaking thermostat, I'd take a look at it. If it is, you should see some fresh fluid on it/coming out of it.

 

I would check near near under the thermostat. Then check near the water pump area near the supercharger. You said its near the intercooler , do you have a picture?

#1 is the water pump connected to the end of the supercharger, #4 is the thermostat housing and its location on the side of the engine.



We have the kits for the thermostat.

All Genuine MINI:

http://www.ecstuning.com/Search/11537596787KT3/



Genuine MINI & Wahler thermostat


http://www.ecstuning.com/Search/11537596787KT4/




We also carry the OEM Genuine MINI Coolant


http://www.ecstuning.com/Search/82140031133/ES196253/



Thanks and I hope that helps.

 

If it's coming down the front of the motor, I would check the water pump flange. You might have better luck removing the front splash guard and looking up from below.

 

Do you think I should just order new hoses as well? I put in "normal" coolant when I did the flush, even after reading posts about doing so. Do you think this had anything to do with my situation? Sorry for my delayed response, I've been out of the country in South Africa for a few weeks.

 

The hoses are usually good unless there is a apparent split or leak from them that can be seen. Its good to inspect them when you have them disconnected. I use the genuine MINI coolant mixing 50/50 with distilled water ( topping off , adding, or replacement ) as it easy to do with the original coolant which most MINIs have, noted by its blue color so you are not mixing coolants, unless your doing a full flush.

If you had a leak before, a flush does not solve the problem. Inspect those areas near the thermostat, and let me know how it goes.

Thanks and good luck.

 

I recently had the same problem after hitting a blown out 18 wheeler tire in the road and it knocked the fan housing loose which rubbed a hole in my upper radiator hose and cracked my thermostat housing. after replacing them its back to normal.

 

I bet you have a leak AND a fan issue....
the leak has to do with the volume of coolant...
But the fact the car starts to get hot as soon as you get off the highway...
I must ask...can you hear a cooling fan?

 

Do you recommend the Genuine Mini or Wahler Thermostat?

 

Either one will work. It comes down to what brand you prefer. Some people stick with OEM MINI and some like the aftermarket. Both have the same rating around ~195 degrees f.

 

Do you think I need to replace the whole thermostat or just the housing? Also, how quickly do you think the parts will get to South Carolina from ECS?

 

Unfortunately I am not near the car at the moment. My question to you is how long after I start the car should I be able to hear the fan engage?

 

If its hot out it kicks on pretty quick. And when i bought the thermostat housing it did not come with the gasket so i had to buy it separate and the gasket comes with the thermostat . I bought my thermostat and gasket at Napa and my housing at advance auto parts.

 

Oh, I had no idea that local shops carried the parts (gasket and housing)... I am about to order a complete t-stat from ECS, I believe it's like $70. How much did you pay for your parts locally?

 

I paid about 50 for the housing and about 35 on the gasket and thermostat