CDT Cooling fan problem/

[tourer]

Taking friends tomorrow to Blenheim Palace in my CDT Tourer, so checked car over. Switched air-con on and short while later saw smoke pouring out of bonnet. Obviously switched off and investigated. Suspected fan or air-con compressor etc. Removed grill and found fan would not rotate easily. As soon as I pushed it round, it sprang free and now rotates ok. Seconds later saw a largish piece of grit in front of fan.
I suspect the grit jammed the fan, causing the smoke, but I cannot be certain.
Tried engine again. Fine. Switched air-con on and fan works and cool air in car. Great.
But do not think fan is running at normal speed, as when I put econ on I can normally hear the fan slowing down and stopping. Now, I cannot, so suspect the fan is not running as fast as normal.
I suspect I have lost at least one of the speeds on the fan.
From memory, I think I have a 3 speed fan as Terry (TSAUTOS) once tested it on T4.
The car was first registered in Aug 2004, but I know it was built in Aug 2002. I've never needed to look at fan problems before, so not conversant with them, but I did NOT notice a resistor (that I have read about) on the fan motor.
I'd be very grateful if the knowledgeable amongst you could advise what is likely to have happened, and what I need to repair/replace.
At the moment the other half not too happy as we have agreed to take our friends to Blenheim tomorrow morning (200 mile round trip) and is worried about the car reliability.
My plans are still to go, but would be happier, obviously, with fully working fan.
Thanks for reading and any advice.

[blowncrv]

General consensus is the CDT will run no problem without a functioning fan.I personally have run mine for some time without any problems.I wouldn't run the a/c but your car should drive without any problem.

[SD1too]

Switched air-con on and fan works ... But do not think fan is running at normal speed, as when I put econ on I can normally hear the fan slowing down and stopping. Now, I cannot, so suspect the fan is not running as fast as normal.
I suspect I have lost at least one of the speeds on the fan.
Melvyn,

I very much doubt that you have lost one of the fan speeds. If the fan runs when you switch on the air conditioning for the first time, then it is running at slow speed which is fine. I think you're half expecting there to be a fault because of what happened with the large piece of grit. It seems to me that you've been lucky and your fan has survived a momentary obstruction which caused it to draw excessive current; hence the smoke. Why not check it now? Start the engine, switch on the air con. and observe the fan running through the radiator grille for a few minutes. If there's no repeat of the earlier problem I'd say that you can go ahead with your plans tomorrow

By the way, regarding the claims that the diesel engine never needs fan assisted cooling, another member recently reported that his fan burst into life after towing a caravan up a steep hill, then remaining stationary for a few minutes. It only takes some hot weather and a high engine load and those who haven't repaired their faulty fans may well find themselves in trouble. In my view all engines, petrol and diesel, should have a properly maintained cooling system.

Simon

[tourer]

Melvyn,

I very much doubt that you have lost one of the fan speeds. If the fan runs when you switch on the air conditioning for the first time, then it is running at slow speed which is fine. I think you're half expecting there to be a fault because of what happened with the large piece of grit. It seems to me that you've been lucky and your fan has survived a momentary obstruction which caused it to draw excessive current; hence the smoke. Why not check it now? Start the engine, switch on the air con. and observe the fan running through the radiator grille for a few minutes. If there's no repeat of the earlier problem I'd say that you can go ahead with your plans tomorrow

By the way, regarding the claims that the diesel engine never needs fan assisted cooling, another member recently reported that his fan burst into life after towing a caravan up a steep hill, then remaining stationary for a few minutes. It only takes some hot weather and a high engine load and those who haven't repaired their faulty fans may well find themselves in trouble. In my view all engines, petrol and diesel, should have a properly maintained cooling system.

Simon

Thanks for replies. The fan IS running with the air-con on, but I still think it is running slower than normal. Usually you can HEAR it running at fast speed in the cabin, when idling. Now I cannot, even thought I can see it is running.
Does anyone know which of the speeds the fan is supposed to run at for air-con purposes?

[SD1too]

Usually you can HEAR it running at fast speed in the cabin, when idling.
That should happen only if your air conditioning is working very hard; for example at an ambient temperature around 30° and a low cabin temperature requested.

If you really do have a 3 speed system and your slow speed has failed due to mechanical damage, the fan motor would stop. The car's electronics cannot detect such a fault and are not programmed to substitute higher speeds under those circumstances.

If you start the engine from cold and press 'Auto' it will be the slow speed you hear. It can only be faster if the refrigerant pressure is high.


Does anyone know which of the speeds the fan is supposed to run at for air-con purposes?
Yes, I know. At slow speed continuously, ramping up to medium (3 speed system) or high speed (2 speed system) when the refrigerant pressure exceeds a certain figure.

Simon

[tourer]

That should happen only if your air conditioning is working very hard; for example at an ambient temperature around 30° and a low cabin temperature requested.

If you really do have a 3 speed system and your slow speed has failed due to mechanical damage, the fan motor would stop. The car's electronics cannot detect such a fault and are not programmed to substitute higher speeds under those circumstances.

If you start the engine from cold and press 'Auto' it will be the slow speed you hear. It can only be faster if the refrigerant pressure is high.


Yes, I know. At slow speed continuously, ramping up to medium (3 speed system) or high speed (2 speed system) when the refrigerant pressure exceeds a certain figure.

Simon

Many thanks, Simon. You are putting my mind at rest.
Just read myself on the CD that cannot be mentioned, that the fan first runs at slow speed when air con first comes on.
I was just worried because after a run, when I get home I switch the air con to ECON and always seem to hear the fan slow down. Maybe just coincidence.
I'll go and investigate more.
The stench of burning motor and the amount of smoke makes me think I am very lucky if I have got away with it.
Thanks again.
Melvyn.

[SD1too]

The stench of burning motor and the amount of smoke makes me think I am very lucky if I have got away with it.
You should definitely satisfy yourself that the fan motor is o.k. before setting off tomorrow. You will need the air conditioning with four people aboard because it's going to be 'scorchio' again. :D

Simon

[tourer]

You should definitely satisfy yourself that the fan motor is o.k. before setting off tomorrow. You will need the air conditioning with four people aboard because it's going to be 'scorchio' again. :D

Simon

UPDATE.
Fan ran for about another five minutes on slow, then died completely.
Air con working while car in motion, but obviously not when car is stopped.
:mad::mad::mad::mad:
Can hear relays etc pulling in (trinary switch?)
Not happy bunny.
Anyone any idea of costs?

[SD1too]

Anyone any idea of costs?
Costs Melvyn? From a retired maintenance engineer? ;)

Bumper off, remove motor end cap and assess. It may be a brush worn to minimum, in which case replacements are available inexpensively. If there's damage caused by the jammed fan blades then the motor may be a write off. In this event you can buy a second-hand 2 speed system from Arctic (complete with gold resistor) or an aftermarket Kenlowe system from Jules. If you go to a garage they will fit a new genuine MG Rover replacement, the cost of which will make your eyes water. It will also have a silver resistor which will fail at some point.

I hope this is helpful. Feel free to come back with more questions! :}

Simon

[tourer]

Costs Melvyn? From a retired maintenance engineer? ;)

Bumper off, remove motor end cap and assess. It may be a brush worn to minimum, in which case replacements are available inexpensively. If there's damage caused by the jammed fan blades then the motor may be a write off. In this event you can buy a second-hand 2 speed system from Arctic (complete with gold resistor) or an aftermarket Kenlowe system from Jules. If you go to a garage they will fit a new genuine MG Rover replacement, the cost of which will make your eyes water. It will also have a silver resistor which will fail at some point.

I hope this is helpful. Feel free to come back with more questions! :}

Simon

Thanks again, Simon.
Very busy at the moment getting ready for tomorrow, and trying to get something to eat (starving and wife out at moment).
In a day or so I will have to have access the fan and calmly assess the situation and decide how to move forward.
Arn't these cars fun as they get older?

All the best,
Melvyn.

[Dragrad]

Thread moved to appropriate forum. Re-direct left in old.