Today i ran a gallon of 100 octane racing fuel through my 2002 stock MINI.
Could this be linked to it running hot?

 

It should not, the octane would not make the fuel burn hotter, it would just make it take more pressure/temperature to ignite.

What were you doing when it was running hot? Did the high speed fan kick on? You can't miss the sound when it does, sounds like a jet engine compared to our little engines.

 

It didn't start driving hot til i had driven some, parked it, and then when i got back in to go get dinner it started. I was driving around and i heard the fan kick on. I didnt think it to odd but i had only been driving for about 5 minutes so when i stopped i checked it and it was to hot to have been driving for that short a time.

 

In a Cooper S, Engine heat up time is really fast. Especially when it is a hot summer day. Super/Turbo chargers create a LOT of heat.

JustaCooper heat up time is a bit slower due to the lack of the heat mongering air compressor under the hood.

I just want to make sure we don't have a mis understanding here. You do mean that the temp Is above 194F/90C correct?. If you are just using the oil temp gauge in the spedo, it should sit about half way up. If you are using the oil temp gauge in the Chrono pack it will read about 3/4 up the gauge.

5 Minutes is plenty of time for any engine to overheat completely if it is not properly cooled. You said the fan kicked on. So that rules that out. Have you checked your coolant level? If it is low you should check the common places for fluid leaks (the Expansion tank lid, the expansion tank centerline, and the Thermostat housing/seals.). And of course fill it up if is low. If none of those things are the problem and you still have problems, we'd start having to get into bit more off the wall things. Low oil/bad oil can cause excess heat (among other things). Check the oil level and color.

that's all the advice i can give. I hope we can help you get this sorted out, I'd hate for a good MINI to have to sit at home because of problems.

 

Even if you were parked for a bit, the temperature drop when the fan isn't running is at a snail's pace. Basically it'll take a few hours to cool off completely.

If you were driving for five minutes slowly, you can get the temperature high enough so that the high speed fan will kick in.

I've been monitoring my own car because I thought I was having issues, but it's just like Agarwaen said.

The high speed fan on mine doesn't really kick in until my scangauge temps read 230, then it cools it down to 215 like clockwork. But the temperature gauge on the center speed (non-chrono) will stay in the middle since it isn't a completely linear gauge anyway.

 

FYI - low speed fan should be kicking in anywhere's from 215-220* ! And works effeciently enough to keep the temps in that range. The high speed fan kicking in at 230* means you probably have a blown low speed fan resistor, and a new fan assembly is required.

Adding to this problem is that most MINI owners think the OEM dash temp guage aft of the fuel level guage will let us know if temps get too hot. Not so. That guage will always read "mid point" once operating temps are reached and stay there until it's too late. By the time it reads "temps too hot", the engine has already over heated. Head gasket and other issues may ensue.

The nature of the (very loud) high speed fan which is very loud as mentioned above, was explained like this.....it's the "oh **** fan". A last ditch effort to prevent you from blowing a head gasket. So technically, you should never hear that fan.....

When we use our AC/Heat, this same low speed fan will come on exactly 30 seconds later, along with the cooling fan for our electric power steering pump. If you suspect a problem with the LSF or the power steering fan or both, just put your MINI up on ramps, keep the vehicle running and secured, then turn on the AC system and exit the car. Wait the 30 seconds and visibly make sure both fans are coming on.

I purchased a TYC fan assembly off ebay for 99 dollars shipped. 1/3 the dealer price and comes with a better warranty, lifetime. Our club mechanic started stocking these as well and has installed litterly dozens of them in the last 6 months and so far not one has been returned. I have also spoken with the distributor as well, ( Georgia I think ) and they have never had one returned to honor that warranty.

Ounce of prevention................

 

Coolant level is good, apparently it just got hot cause i drove it again today and everything ran fine and it didnt get to hot. Also i was monitoring the temp gauge when it got hot.

 

That, I didn't know. More reason to pick up a Scangauge. Also to note, If you were running the A/C the high speed fan is supposed to come on.

 

Well it was extremely hot, so the AC may have been getting it. Thanks guys. :D

 

So the high speed fan kicking in at 230 is probably a blown low speed resistor? Figured it might have been something like that. Least when driving, the temps stay under 200 unless I'm stuck in traffic and that fan at least cools the car back down to 215 for me. Could it be an issue with the thermostat also?

Guess I'm part hunting. Was looking at rock auto, but I'll do some more searching since I heard that '02s have different part numbers because the part wasn't exactly the same through all the 1st gen years.