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Having some trouble to get the noise down for the MoT I thought i take out the Radiator Fan Blade to Look if it makes any difference and indeed the Car is a lot quite at high revs...

Wile driving the temperature only rised about to 95*C

When switching the electric Fan the temperature goes down to 80-85*C

Does someone here has done some experience with this?

What's the amount of Power gained, less noise, temperature troubles ect?

The noise has to be measured asp...

The fan is too noisy for the MoT..??

Isn’t this just overreach by the testing station?

Fanfani is in Switzerland.

Due to the always more and more black bearded idiots wich run illegally tuned BMW 's and other performance Cars with Pop&Bang software on their ECU the Police and MOT people are oversensible to everything "noisy ".

So almost every Car wich appears to loud will be measured.

All Cars here were homologated. In my case, 80dBA measured laterally 7 meters away from the Car...

Switzerland is a beautiful place but they do have some rules !

my GT over the past years shows 95deg; on the Smiths Capillary Gauge .. this cars normal running temp ..have tried many things to lower that temp reading but the car has always driven ok even in past hot summers then showing over 100 .. but that engine has not boiled up .. (yet). so i do wonder about the accuracy of that Smiths Temp Gauge ?
My twin H4,s are the greatest source of noise with the open Intake... one day i will cut up my spare "standard" Hs2 Airbox to fit these H4,s in the hope to lower this noise .. but this would be like cutting the corner off an expensive antique table just to get it to fit into a corner

As I have said many times over the years and recently, the standard gauges in our minis are really just simple 'indicators about what's going on' gauges

Even when the factory fitted an electric fan as standard to 1990's Mini Coopers with a side mounted rad they still retained the engine driven fan. The electric fan under the wheel arch usually cuts in automatically when caught in stationary traffic especially on a warm day.
The last MPi Minis (excluding Japanese export SPi) had a front mounted rad with an electric fan only like most modern cars. This was done to move the rad into airflow when moving, while reducing the 'drive by' noise which was required to meet new European legislation. The fan on Minis is quite noisy, the loudest are very early Minis with the metal 4-blade fan which make a very distinctive noise, much reduced by the later metal and plastic multiblade fans.

I have fitted a 1990's Mini electric fan to my earlier Mini under the wheel arch but controlled by a manual switch and retaining the original engine driven fan. Sometimes in slow moving traffic I have to switch on the electric fan to bring the temperature gauge back to normal but on a warm day that is more comfortable than switching on the heater for additional cooling!
If you do wish to try removing the engine driven fan I would suggest replacing the standard 'cold/normal/hot' electric temp gauge with a capillary mechanical temp gauge so you can monitor the engine temperature reading more accurately.

WATER TEMP MECHANICAL SMITHS GAUGE:-
https://www.minispares.com/sib422-water ... 5mm-sender

For reference, as said above I fitted the electric fan that was factory fitted to the mainstream Rover Mini Coopers in the 1990's (see photos below). On the Rover Cooper it was fitted under the wheel arch with a large fan sized hole in the inner wing. However you can mount it to the earlier Minis inner wing (with the rad vent slots) without cutting a large hole, by simply adding small spacers to each of the 3-off electric fan mounting studs/bolts, to space the fan blades a few millimetres away from the raised edges of the inner wing slots, so it can blow/suck air through the slots onto the rad.
It seems to work well for me better than the aftermarket type fans. I bought the Rover electric fan secondhand off ebay a few years ago for a good price. They were NLA new for some time and were in short supply but Minispares now sell them....although the price seems quite high for a new one.
RADIATOR ELECTRIC FAN ASSY LAST CARB/SINGLE POINT INJ ONLY:-
https://www.minispares.com/pgg10058-rad ... t-inj-only

There is no electric fan that can do the job on it's own. The mechanical fan pushes around '3HP' worth of air volume and it needs all of that. The best Electric fan you might find is about 750 watts and most are around the 400 watt mark.

I don't know what year your Mini is, but surely if they were sold in to that market with the mechanical fan and they were accepted that way at that time, they would continue to accept that today.

Several mechanical fans were fitted over the years. Depending on what you have presently, you might make it quieter by swapping. The later yellow plastic one is supposed to be the quietest, I believe?

I did read somewhere recently that another reason - apart from economy - the last Mini's were fitted with 3.1FD was to reduce "drive-by" noise by lowering engine rpm. This had become a requirement for type approval by then.

With respect to what Spider Cris says (last para, above) with respect to how the car was built and the regulations that applied that applied at manufacture. We must only now assume the the Swiss have change the noise laws to incorporate what we call RETROSPECTIVE LEGISLATION.

That's a bit like the UK making out emission laws apply across the board.

October 1st 1996 - Rover Press Release
"Mini moves into a new and quieter age with the 1997 models. By combining engineering changes that meet stringent new 'pass-by' noise regulations with substantial improvements to cabin acoustic insulation, the latest Minis have become the most civilised yet.
A significant technical change is the repositioning of the radiator to the front of the engine bay ensuring compliance with the pass-by noise legislation and enabling major gains in refinement at all engine and road speeds.

The EC directive on pass-by noise (92/97/EEC) that all post-October 1996 registered cars must meet, demands a maximum of 74dB(A) measured by a special test procedure. Since the previous limit was 77dB(A), this may not seem a big reduction, but because decibels are plotted on a logarithmic scale, it actually represents a halving of the noise level. Reductions of up to 3dB(A) in the critical 3250-3500 rpm range mean that motorway cruising at the legal speed limit is twice as quiet! In order to achieve this, the 1997 Minis feature higher gearing, a new front-mounted radiator with electric cooling fan, and a rear exhaust silencer box. For lower internal noise levels, a 2.76:1 final drive ratio raises the overall gearing by 16% compared to the previous Mini Cooper.

Interior sound deadening measures include damping pads in the roof, plus the extra absorption effect of the new foam-backed fabric headlining which help to tune out the 'boom' effect at higher engine speeds. Extra sound-path sealing around the top of the bulkhead and the A-post areas keeps engine noise out and there is new sound insulation around the fuel tank and boot area to eliminate any possibility of whine from the high pressure fuel pump. The rear seat bulkhead is now solid, without the former blanked-off central aperture. Improved acoustic insulation from road noise results from the new moulded one-piece floor carpet."
Rover Mini MPi Launch Documents:-
https://www.roblightbody.com/official-l ... ments.html

Little update:

I made a 300km+ trip yesterday evening to the south of Switzerland, mainly using the Swiss Autobahn. (120km/h)

I started 15.30h local Time at a temperature of about 17*C and over the most of time the temperature didn't go over 100*C on my Capilar Speedwell Temp Gauge.

In the Gotthard Tunnel (17km long... and inside temp +35*C) the temperature get up to 110*C wich needed the addition of the heater, otherwise the temperature stayed very stable.

I think i will fit a temperature controlled switch to get the temperature controlled...

Polarsilver wrote: ↑Sat Mar 01, 2025 10:09 am my GT over the past years shows 95deg; on the Smiths Capillary Gauge .. this cars normal running temp ..have tried many things to lower that temp reading but the car has always driven ok even in past hot summers then showing over 100 .. but that engine has not boiled up .. (yet). so i do wonder about the accuracy of that Smiths Temp Gauge ?

Peter Laidler wrote: ↑Sat Mar 01, 2025 12:14 pm As I have said many times over the years and recently, the standard gauges in our minis are really just simple 'indicators about what's going on' gauges

I'll just put on my Teaching hat........
The radiator cap on a mini rad is a pressure cap or in simpler terms it holds the coolant under pressure.
You should really be running a 15psi cap !
The boiling temperature of water at 15psi IS NOT 100 degrees centigrade it is about 120 degrees

Couldn't have said it better. Go to the top of the class Smiffy!

At 120kph any fan would be a hinderance to the airflow compared to the air coming through the grille

timmy201 wrote: ↑Fri Mar 07, 2025 9:20 pm At 120kph any fan would be a hinderance to the airflow compared to the air coming through the grille

No. The fan is needed at all speeds. There's next to no air pressure drop from the engine bay to the wheel arch, so there's next to no air flow.

Spider wrote: ↑Sat Mar 08, 2025 10:59 am

timmy201 wrote: ↑Fri Mar 07, 2025 9:20 pm At 120kph any fan would be a hinderance to the airflow compared to the air coming through the grille

No. The fan is needed at all speeds. There's next to no air pressure drop from the engine bay to the wheel arch, so there's next to no air flow.

I’m sure I’d read that on the internet somewhere so it must have been right my mistake

When I was a young man, I figured that there would be enough holes around the bottom of the engine bay that the grill opening wasn't really needed. I had been having a lot of trouble with water in the distributor, so I put a layer of black plastic film on the back of the grille. I was wrong. Overheated in no time.

Tim