Hi guys I am brand new to the forum and a brand new Mini cooper S owner. Ive been wanted one for years and finally sold my BMW Compact and bought an r53 last week. For £4000 I bough an 02 Cooper S with 58k on the clock.

I was really happy about the car until the other day I was sat in traffic and it overheated and coolant boiled over. Since then Ive searched all over the forums for probable causes and hoped it was just the usual problem with the fan not working.

I took it to a local BMW specialist in Sheffield anyway so they could check the fan and replace it. However they had it over night and today have phoned me up to say they expect the cylinder head to be faulty. As the fan is coming on but not before the coolant already boils over. They also believe that its failing a pressure test.

Since Im a new owner I'm so disappointed to be looking at large garage bills so soon into ownership but Im also a little worried about being taken for a ride by the garage.

They have quoted me somewhere in the region of £1000 to have the head removed, sent away, tested and refurbed and refitted (if thats whats required).

Do you think thats a reasonable price and that it sounds like a probable cause to the problem?

Also I thought that if they where taking it to bits anyway and since I was already thinking about some modifications, that perhaps this cloud could have a slightly silver lining and I could get some bits done at the same time to save on labour costs. Was immediately thinking about a 15% reduced pulley but can you guys sugest anything else that would be worth doing? I wouldn't want to go mad on it but would be happy for it just to be noticeably quicker than a stock r56 one (to shut my mate up!).

Any suggestions or advice would be greatly appreciated, thanks guys.

I would get a second opinion the cause could be many other things which don't require removal of the head on your MCS.
More things to check first here:
Solving MINI Cooling Problems.......... - Forums (http://forum.minicooper.org/showthread.php?t=13263)

Thanks think I will. They recon they tested the head with a die that shows weather it's mixing with the coolant or not?? So don't even think they've done a proper compression test. Since its been running fine over the past few days I worked out how to see the actual cooling temp on the computer and it's regulating nicely. Out of interest at which specific temp would cause the fan to actually come on? Want to check what temp the water boils over.

Phone the garage but they had already removed the head.

They confirmed that the head gasket had slightly blown through between two of the cylinders. Not a lot I can do about that guess these things happen!

Phone the garage but they had already removed the head.

They confirmed that the head gasket had slightly blown through between two of the cylinders. Not a lot I can do about that guess these things happen!


They removed the head without you giving them a go-ahead on the repair :confused:


Sounds sus to me! , i know for a fact my mechanic would check everything else before removing the head and he would most certainly speak to me first!

Sorry I had given them the go ahead in the morning but they weren't sure if they would have the ramp space until tomorrow to actually get started.

They were fairly sure that something was wrong with the head and apparently used a technique involving die to see if coolant leaks through but from how it was driving you really wouldn't have noticed unless it got worse I guess. Ive never heard of this technique though for testing the head?

Also not convinced if they know about the fans two speeds. They think its working but only after it boils over so Im guessing thats the fan coming on high speed. Will raise the question once its back together and maybe sort out the fan myself anyway.

The garage are well known and do seem honest. I know the gaskets are prone to failure from overheating so dont think I can argue. Just miss the car already its rubbish not having it for long and losing it to a garage for maybe a week :(

Quote from my link above:
"The cooling fan first stage speed is like a base point to provide a constant regulation of temperature while 2nd stage fan is for peak temperatures reached when car is stationery or under load, it quickly brings the temperature back to the regulation zone.
At 105C the low speed should be on
At 112C the low and high speed should be on together
OR if the refrigerant pressure from the A/C compressor is good and Air Con is on then the fan should also be on."

"In a perfect Mini cooling system, the low-speed fan will come on (and stay on) when you turn on the A/Con - always. If the fan does not come on (low-speed) when you turn on the A/C, but then comes on at high-speed after a few minutes (you'll know it's on high - very loud), those are the symptoms of a burned-out resistor."

The blown head gasket test is done with a special dye added to the coolant which changes colour if it detects exhaust gas contamination in the coolant, thus indicating the head gasket has blown between a cylinder and a water-way in the head/block joint. If they did the test and got a clear result then the head gasket would almost certainly be the fault and £1000 is not far off for work/parts involved on a MCS. What you must check after is that there is nothing else at fault, like the lack of the 1st stage fan cutting in, faulty pressure cap, thermostat fault or leak which may have helped cause the original overheating and damage to the head gasket in the first place. However, it is possible for a head gasket to fail without any obvious cause being found.

Thanks for that but I dont actually have AC, but the big sunroof instead.

Certainly feel better know I can get the computer to read actual cooling temp just to keep an eye on. Never heard of a car with a temp gauge that shows normal temp most of the time just to look right even if the car is on the verge of overheat. Useless!

Thanks for that but I dont actually have AC, but the big sunroof instead.

Certainly feel better know I can get the computer to read actual cooling temp just to keep an eye on. Never heard of a car with a temp gauge that shows normal temp most of the time just to look right even if the car is on the verge of overheat. Useless!

More and more cars have this type of 'dumbed down' gauge so drivers don't worry about variations of temp and many now have no gauge, only displaying a warning message to visit dealer workshop!