Hi all, i recently bought a 04 R53 with 160k miles from Detroit, MI

I'm using an OBD tool connected to my cell to monitor the coolant temp, it is usually between 195 and 205F which from what i have read is normal.

If im stuck in traffic and crawling around in 1st gear, the temps tend to rise after 7-10 minutes. The max i have seen is 230F after which i started the cabin heater which brought down the temps to around 200F. The temp needle in the cabin did not move the entire time.

I'm pretty certain that my water pump is on its way out. Is this true?
Also, how long/how many more miles do you guys think will the water pump last before critical failure? I will be in a region where the ambient temp will not go above 30F for the next 4 5 months.
The car is completely stock and I have put in new plugs and am changing the oil on a regular basis (if it makes a difference).

P.S.: The MINI community is awesome and I have learnt quite a bit from the forums and from YT. Thanks guys!

EDIT: The high temp fan is working. I can hear the when I turn ON the AC

 

The temp needle in the car is not much better than an idiot light. The high speed fan set point is 234, what was the outside temp when you hit 230?

The water pump rule of thumb is about 70k miles.

 

The outside temp must have been near 25 30F.
I've had the same issue with the AC ON at different times throughout the last 3 months that I have owned her(at 200F and then the temps started rising). So, I think that the cooling fan is not the issue.

The 70k is for the overall life of the pump right?

Thanks!

 

Welcome to the forum

 

Thanks!

 

The pumps usually start leaking when they start to go.

 

Does the coolant leak when the car is standing around or only when it is running? (I'm guessing the latter)
Sorry for my noobness!

 

Would depend on how bad the pump is. The pump is below the driver side supercharger horn. Have to put the car in "front service mode" to gain access. Thinking the shop price is around $700.

In some instances the leak is the t-stat housing and not the pump.

 

I have checked the tstat housing after driving for a while. I did not see any moisture, so it should be good.
Would I see the whiteish residue left by the coolant on/near the water pump if I put the car in "front service mode" ?

 

I don't see you check both high and low speed.

 

I do not know how to check if the low speed fan is working or not.
I read somewhere that having only the high speed fan is sufficient to maintain temps.

 

Use that temp gauge on your tool. The low speed fan with the A/C off should come on about 220-222. Then it will cool down to about 211 and shut off. The high speed stg 2 fan usually comes on about 234, but that is pretty late.

We normally just test it by activating it through the computer to see if it will come on or not.
Also often you can just replace the resistor and make it work.
https://www.waymotorworks.com/radiat...0-r52-r53.html

 

Thanks for the detailed explanation!
I'll try it out when I get a chance

 

+1 for low speed fan is out

 

I did a little test yesterday: (ambient temp was 45F)

I drove around till the coolant was at operating temp (195 - 205F). I then parked the car and let her idle.
The AC and blower were OFF the whole time.
After about 5 6 minutes, the coolant temp started to increase. Around 220F, me and my friend heard a whirring sound in the car. We poped the hood and the sound was coming from the radiator. This I'm assuming the low speed fan starting. However, contrary to what WMW suggested, the temp did not drop. Temp kept increasing. It stabilized at 226F for about 30 sec and then again started to increase. When the temp reached 233F we heard a loud vacumming-type sound. This was the high speed fan starting, after which the temp dropped to ~215F very quickly (like in 4 5 sec).

Questions:
If the low speed fan is working, why would the temp not drop as is expected?
I'm curious: I find it interesting that the temps dropped so quickly after the fan switched to high speed. Is the temp sensor located just after the radiator?
When I had the issue in traffic, I was crawling around in 1st gear. This would mean that there was a little bit of load on the engine. How much do you guys think this will affect the whole situation?

 

What was outside temp?

Parked and at idle depending on the outside air temperature the low speed fan may not be able to keep the coolant temperature steady and or decrease it. Thinking the exhaust gas temperature is anywhere from 700 to 1200 degrees Fahrenheit. Without adequate air flow and/or cold temperature the low speed fan is not enough.

Somebody with more knowledge should chime in if I am blowing smoke.

 

Outside temp was 45F

 

Hmm, thinking how temperature dynamics may be involved as there is rule of thumb in building energy management that once the temperature is below 40 something, the structure can longer retain heat but begins to lose it. Wondering if that temperature has anything to do with a car being able to maintain proper cooling without air being forced through via driving.

There is an engineer someplace that can take the size of the radiator, the total surface area of the fins, the coolant flow rate, the temperature of the coolant, the ambient temperature and the FPM going through the radiator to calculate what affect there will be.

 

What are you studying to be? Most people would have no thoughts about the temperature of the their coolant let alone even know what coolant was.

 

Im a Mechanical Engineer, but have no experience working with cars

 

That sounds resonable
My question is, in your opinion do you think that this behavior is normal for the MINI? i.e do you guys think that I have a problem?
The way I interpreted WMW's comment is that the low speed fan should usually cool down the car when the outside temp is reasonable (I would guess till the outside temp is below 70F)

 

Car or Chiller/Boiler plant, all the same thermal dynamics.

 

I saw nowhere did you mention or consider the thermostat may have failed. It should be up your alley being an ME.

With your symptoms the thermostat opening too late, or sticky is a real possibility.

 

Like I said in my previous post, I have checked the thermostat after driving for a while. There was no moisture on or around it which makes be believe that it is working correctly.
Also, if the thermostat was opening later than usual, won't that also affect the temps when I am driving around normally? I would expect it to run at least a little bit hotter than normal.

 

A sticky thermostat will not necessary cause the housing to leak. BTW, I did a web page search for "thermostat", and saw no hit.

I am not convinced that you verify the low speed fan functionality. You inferred a lower level sound and assume it is low speed fan coming on.

You can perform a easy test for the low speed fan by measuring the resistance WRT ground at the connector. Both high speed and low speed hot side should read like death short. If one is open, it is 99.99% the resistor has gone kaputt.