Can you repair NoResistor fan OR add a Resistor?

[rik007]

Hi I've got a 2003 CDTi saloon, it has a NO Resistor fan. The fan can be turned by hand through the grill but does not work with aircon or demist.

Is it possible to repair this kind of fan? i.e. add a resistor?

I'm a bit confused as to why you can add a resistor to one that has an old duff silver resistor but not repair a Resistor unit.

Jules I know sells the fan and resistor kit, but I've always wondered why you cant repair the original units if the motor is still good.

With thanks, Rich.

[Astraeus]

Originally Posted by rik007

Hi I've got a 2003 CDTi saloon, it has a NO Resistor fan. The fan can be turned by hand through the grill but does not work with aircon or demist.

Is it possible to repair this kind of fan? i.e. add a resistor?

I'm a bit confused as to why you can add a resistor to one that has an old duff silver resistor but not repair a Resistor unit.

Jules I know sells the fan and resistor kit, but I've always wondered why you cant repair the original units if the motor is still good.

With thanks, Rich.

In short , yes you can. But only if you know for certain that the fan motor is actually working. Does it every work/ come on or is it dead on all speeds.
There is a how to on here somewhere about how to change the three speed wiring to make it two speed with resistor. You may also have to change one or both of the relays in the control box. It can be done if you are handy with a soldering iron. Fairly involved job with bumper etc off.
Jules does the required parts.


Chris

[T-Cut]

Originally Posted by rik007

Is it possible to repair this kind of fan? i.e. add a resistor?

The earlier fan has a 3-speed motor. The later (resistor) type is 2-speed. The usual issue with the 3-speed is worn out brushes. Replacing these is worth looking at. You can't fix it by adding a resistor. There are lots of discussions on brush replacement.

I'm a bit confused as to why you can add a resistor to one that has an old duff silver resistor but not repair a Resistor unit.

The OEM resistor in later 2-speed systems is under powered (50watts, and later 75watts) so it burns out. This can't be fixed. You replace it with a bigger, higher rated resistor (100watts).

Jules I know sells the fan and resistor kit, but I've always wondered why you cant repair the original units if the motor is still good.

If the 3-speed motor is still good internally, then a brush replacement will bring it back into service. If the commutator or brush holder plate is irretrievably damaged, it can't be fixed.

The later 2-speed fans are plug and play for the earlier types. Diesels have unique control electronics and should only be swapped with another diesel system.

TC

[SD1too]

A very clear and thorough reply from T-Cut there Rik. So what you need to do first is to remove your fan motor and open the casing to see if all it requires is a couple of new brushes. Arctic has posted some superb pictorial guides to this repair. Buy your new brushes directly from Engineering Carbon Products (click on specific 'Rover 75 3 speed fan' in grey panel). Avoid inferior products from e-bay sellers.

If you have any further questions Rik, just ask.

Simon

[Arctic]

Originally Posted by T-Cut

The earlier fan has a 3-speed motor. The later (resistor) type is 2-speed. The usual issue with the 3-speed is worn out brushes. Replacing these is worth looking at. You can't fix it by adding a resistor. There are lots of discussions on brush replacement.



The OEM resistor in later 2-speed systems is under powered (50watts, and later 75watts) so it burns out. This can't be fixed. You replace it with a bigger, higher rated resistor (100watts).

The later 2-speed fans are plug and play for the earlier types. Diesels have unique control electronics and should only be swapped with another diesel system.

TC

Replaced a fan for a local owner recently as his fan was not working on any speed checked on our T4, most of the time I have found that if all speeds are not working then either the commutator and or the holding plate will have burnt out, as you can see from the photo's below this was just the case with the owners fan.

Note all the brushes are in tact therefore the fan motor must have got stuck some how and burnt out both the brush plate and commutator, the generated also caused the brushes to become brittle and have air line cracks in them, they must have started to break up as I found segments of brush loose in the fan motor once I had taken it apart. Arctic

[tony062622]

Originally Posted by T-Cut

The earlier fan has a 3-speed motor. The later (resistor) type is 2-speed. The usual issue with the 3-speed is worn out brushes. Replacing these is worth looking at. You can't fix it by adding a resistor. There are lots of discussions on brush replacement.



The OEM resistor in later 2-speed systems is under powered (50watts, and later 75watts) so it burns out. This can't be fixed. You replace it with a bigger, higher rated resistor (100watts).


If the 3-speed motor is still good internally, then a brush replacement will bring it back into service. If the commutator or brush holder plate is irretrievably damaged, it can't be fixed.




The later 2-speed fans are plug and play for the earlier types. Diesels have unique control electronics and should only be swapped with another diesel system.

TC

Just had mine checked out yesterday by Marinabrian,although mine is a facelift 05 cdti it has the 3 speed fan.Brian found no speeds working.I cant afford to take the car off the road(no other transport) to check the motor out and then have to either renew parts or source new motor, I have sent email to Jules to order one,also ordered condenser and new intercooler hoses.May also try and source a good inter cooler as fins all flaking on mine.Busy weekend next week.

[rik007]

Thanks every one for EXCELLENT info

Very helpful at clarifying the options available for the types of fan.

My fan does not work at any speed, however it does turn bu poking a stick through the grill. I suspect it may well be goosed given Artic's photos; mine could well be the same.

So its bumper off time and open up the motor .....

Will update when I have mine out on the bench.

Rich.

(my wallet is aching)

PS was hit by a stone flicked off a grass cutting tractor the other day. Went off like a bullet as it hit the rear door drivers side. If it had gone through my open drivers window at head height I wonder if I'd have survived. So Highways England will now take 90 days to make 'an assessment'. The garage quoted £350 +vat, they said they car would probably be a right off!! Which is an annoyance having just replaced the clutch and thinking about the fan issue. Hey ho some you win others kick you in the trollies

[SD1too]

Originally Posted by rik007

My fan does not work at any speed ..

Rich; if it's a 3 speed system you cannot check the fastest speed without a T4 so no assumptions can be made about the condition of the motor (unless your coolant has exceeded 112 degrees which I doubt as you own a diesel).

Before you get your tools out have you checked that the fuse feeding the motor relay coils is intact?

Simon

[Astraeus]

Here is the how to

Change 3 speed fan into a two speed with resistor. It can be done and in fact I have done it.
However as said you can only successfully do this if the fan is working on high speed. Your fault does sound a bit like motor failure. Need T4 to check top speed working. It can activate the three speeds in turn.

https://the75andztclub.co.uk/forum/s...d.php?t=209950

[rik007]

Hi, thought I'd tackle the fan today. I have got the fan surround unbolted but I cant workout how to remove the unit as the AC pipes are in the way. The fan housing hinges around them a little but its not enough to get at the motor I suspect.

Am I missing a trick here?

I'm hoping to check the motor and if its brushes, get them replaced.

Many thanks, Rich.