Cooper D - Cooling Fan on in freezing temperatures

[paule3]

Quote: Originally Posted by supa-dupa-cooper (original)

I dont miss this annoying Cooper D trait at all!! The cooling fan on the S does come on but only when it needs to and not at every single opportunity like the D did. You'd think there would be some way to at least make it quieter and not so embarrassing!

Mine doesn't do it that much any more. Most of my trips are in town (work is only 4 miles away), but now I make the effort to take the car for a run maybe once a week and that's done the trick

[Wipeout]

Since originally starting this thread, I've made a few observations.

Driving my car hard, on hill roads, on hot days, revving the engine hard, doesn't cause the fan to come on.

Recently I've started to do long distance commutes (40 miles or so each way) and I never hear the cooling fan come on.

I previously did shorter journeys and drove gently, so perhaps it is just related to short journeys?

[paule3]

Since making the effort to take mine for a run every week it has made a difference and the fan hasn't been coming on.
From what I gather the long runs are best for it as the engine gets warm. As short distances don't really get the engine as warm.

[Super_Dooper_Cooper]

I can confirm that the gearing on the Cooper D prevents the exhaust stream from reaching soot-burn temperatures during colder weather.

The absurdly high 6th gear only allows the engine to rev at around 2000rpm at motorway speeds.

I have worked in the LGV/HGV industry on CRTs which are similar to the DAPs (Diesel á Particulate). Goods vehicles rely on large engines chucking out high temperatures and a pre catalyst to generate a high NO2 loading in the exhaust stream.
The mini is a victim of its own efficiency and does not generate high enough temperatures when in steady state (cruising) conditions.

I have had the hovercraft a few times and my driving is 95% M1 motorway with the cruise set at 70mph. (btw, this achieves 71mpg for all of those people moaning about poor fuel efficiency).

The mini system uses a fuel bourne catalyst system to help, and alters the ignition timing to promote NOx production at times of high filter loading. This makes the engine run hotter as a result and I assume that the ECU brings the fan in to aid air circulation in the engine bay.
The increased NOx production (with bonus added temperature) gets passed through the cat/filter system where NOx --> NO2 happens and the soot (carbon) is oxidised by the NO2.

Hard acceleration prevents this as the filter sees higher temperatures.

In short, there is no fault. The fan comes in to make sure air is circulated around the engine bay during filter purge conditions. The rough engine noise is the altered ignition timing due to changed diesel injection, recirculation valve settings, to achieve higher NOx output.

DON'T WORRY!!!!!

(the burning smell is fuel bourn catalyst and carbon combusting in NO2 - it stinks!)

I've got 6k miles under the car since September 1st, I'll look in from time to time and hopefully all should still be well.

[Super_Dooper_Cooper]

Problem Solved!!

I called Mini Assist out for a heater problem (I have aac and it got stuck on very hot - oven like!).

The same morning on arriving at work (M1, 70mph, 0°C....etc.) the fan was wailing away.
When the bloke plugged the car into the computer, I asked him about this and he was clueless: His answer was that he didn't know because he doesn't see many Cooper D's due to their reliability.

After a little push, he went through the computer and brought up the regeneration data for the cat-filter system. The time since an active regeneration cycle was 0 miles, i.e. it was doing it that morning.

It is a normal part of how the Cooper D works unfortunately, but the guy did say that the car SHOULD do this at motorway speeds, which begs the question: When I travel such a massive distance on the motorway (140 miles/day), why do this when I get to a town/city!!

[Yellow/Black OneD]

Yes, it is the old Particulate gubbins (Technical for don't really know what it does) doing its job, and by the way, the auto stop-start doesn't work when it is going through that cycle! You will get it kicking in more often if you drive steady or short miles as the engine/exhaust temp doesn't get hot enough to burn the excess particles in the filter!

My dad has got a diesel Jag and it does just the same thing, and as he does short journeys it does it quite a lot!