1st Gen R53 Cooper S Most liked posts in thread: Overheating problem?

A resistor for the radiator fan can fail, it's been known to happen even in the winter. Another issue, on early models the power steering fan and the radiator fan shared the same circuit, if the power steering fan seized it could blow the fuse serving both fans (a TSB was issued for this problem), but a fan bracket melting sounds like something was lost in the service explanation. Nothing on the radiator will melt due to convective heat from the engine.

 

First perform a bleed tonight, adjust the expansion tank fluid level after the engine is completely cold, then install a new cap when you get the chance. If it occurs again, we'll go from there.

 

Make sure to bleed at both locations.
Also, what kind of rpms were you running in your spirited driving? Is it possible to over spin the water pump due to really high rpms and a redux pulley? I get this or at least the same effect on my car. The temps seem to be fine regardless of the ambient, but if I keep the rpms too high for too long(i.e. seconds), the coolant burps out of the cap and makes a little mess.

What is your rpm limit?

 

:cornut:My story(08 R56 MCS/JCW 45kmi still under warranty) is some what similar(including Scan Gauge II saying normal 200-220F temps) but she didn't blow out coolant until engine turned off in drive way. Then coolant tinged with oil(really)would bubble up into over flow tank and out onto drive way. Along with 2 small "drip/drip" oil leaks.Mini of Dallas(good people)found/fixed/are fixing:
1.blown right front axle seal
2.oil filter housing to block gasket/seal(not filter cover to housing gasket)
3.blown head gasket
4.are now checking for head warpage
I'll know more on Mon 14Mar11. Any way......that's what's going on with Mini Margi. Hope that the info helps.

Jasonopcorn:opcorn:opcorn:

 

good idea............waiting to hear...........opcorn:opcorn:

Jason

 

Checking if the tank can hold pressure is useful if a tank leak is suspected, I thought the issue here was the cap spewing, so you need to check if the cap can hold pressure.
From RealOEM, retails for...
No.__Description ____________Supplement_Qty_Part Number__Price
01__Cooling water expansion tank______1____17137529273___$34.35
02__Cover lid_______________________1____17107515499____$9.03

If, in fact you need a new one.

Hope you come back clean after the drive. Good Luck.

 

Got it. Well, the tank test certainly couldn't hurt, and now you know it is good. I have seen many posts about how crappy the tank is and how it always leaks, etc, etc. Mine is 5+ now and has yellowed a bit, but I am still waiting for it to fail. They can't be that bad.

Actually, I occasionally experience the same symptoms. Sometimes it spits upon the track, or on the street, and sometimes not. For me when it happens it seems to make a big mess, but the fluid level doesn't really seem to change, I dunno. It does not seem to be temperature related, and so I just trying to consider more crazy ideas like rpm.

I might just order a new cap, not really an expensive part replacement.

Hope you get yours resolved.

 

What criteria do you use to evaluate this? Color? Voltage conductivity? Curious...

 

Here's another method for testing the age of the coolant:

from Doug's Domain :: BMW E36 Coolant Flush DIY

 

:nonod: I get Mini Margi(08 R56 MCS/JCW) back tomorrow from the dealer. Fixed under warranty(@45kmi). What you are describing are the exact same symptoms that Margi had with a blown head gasket.She also had other things that the tech caught and fixed incidentally. But the symptoms of not over heating while driving(Scan Gauge II showed 190-205),back to the drive way,turn engine off. Then,in the drive way, no cooling fan comes on but she vomits coolant on the drive way, 8oz or so, not much. Head gasket(at least in Margi it was). Hope yours is a mere glitch but I doubt it.
(run it by k-huevo and see what he thinks,couldn't hurt)

Jason

 

Jason, my '09 JCW runs at 220 degrees most of the time, which I am told is normal for an '09. Scan Gauge II also.

 

:cornut:Yes. The point was that it was NOT over heating while running but still vomited coolant after shutting the engine down because engine exhaust over pressurized the cooling system through the blown head gasket.

Jason

 

Overheating

:cornut: Scottinbend, I hope that your overheating problem is solved. Mine is. Margi is back and motors like before/no problem. After discussions with the tech, the blown head gasket released high pressure cylinder gas into the coolant system which for some reason caused her to lose her coolant after the engine was turned off and sat for a few minutes. I don't quite understand the logic there(Boyle's law, hot gas more volumious than cooling gas) but they replaced the head gasket and problem solved.Good Luck!

Jasonopcorn:opcorn: