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Old 20th September 2021, 16:25   #1
chicochapman
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Default Radiator fan still not working!!

Its a 2004 2.5 KV6
Having just fitted new brushes to the fan motor, I was disappointed to find it's still not working. I did the demist test and to be doubly sure ran the engine until the temp gauge started moving to the top but no result.
The motor is connected by 4 wires - Purple, Grey, Red and Black with no resistor. There's no evidence of burning in the control box and the fuses and relays in the engine compartment fuse box look fine.

I've tried connecting 12V negative to the black spade in the multi plug and touching 12V positive to the other wires( in the control box) in turn but nothing happens. Does this mean the motor is goosed?


If so, I am now confused as to the correct replacement - Rimmers show

PGJ 000100ASSY being identical to mine but superseded by PGJ 0001000 which has the resistor and a snip at only £432.42!
Any advice gentlemen, would be greatly appreciated.
Malc
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Old 20th September 2021, 18:00   #2
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Try this link: https://www.the75andztclub.co.uk/for...d.php?t=111790 post 3. I've used this very technical guide many times.

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Old 20th September 2021, 18:43   #3
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Hi Malcolm
This will fit your car ok

https://www.ebay.co.uk/itm/274093698...wAAOSwstJZT~zH
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Old 20th September 2021, 19:39   #4
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Thank you Vitesse -bench tested according to the diagram - absolutely dead
Thanks Arctic for the link - should be here in a couple of days.


I'll probably take the old motor apart next week, just to see if I can see what the fault was.


Malc
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Old 21st September 2021, 08:33   #5
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Quote:
Originally Posted by chicochapman View Post
I've tried connecting 12V negative to the black spade in the multi plug and touching 12V positive to the other wires( in the control box) in turn but nothing happens. Does this mean the motor is goosed?
Hi Malc,

Your motor should have run with the thick black to battery negative and the thick red to battery positive. If it didn't then there's still a problem with the motor. Here's a checklist which may help:
  • Was the motor commutator clean and smooth?
  • Did you buy the new brushes from Engineering Carbon Products Ltd. in Croydon?
  • Are you happy with your soldering?

It's a pity that you've already spent £200 on the e-Bay 2 speed system with silver resistor (which you will need to change for a gold type).

Simon
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Old 21st September 2021, 20:00   #6
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Hi Simon,
Brushes from Croydon, soldering ok but commutator burnt and concave!!


Will it run with just the silver resistor?
thanks,
Malc
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Old 21st September 2021, 20:04   #7
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Quote:
Originally Posted by chicochapman View Post
Hi Simon,
Brushes from Croydon, soldering ok but commutator burnt and concave!!


Quote:
Will it run with just the silver resistor?
thanks,
Malc
Hi Malcolm.
The fan you have bought will run with the silver resistor and most likely for at least 75,000 miles or more that is the range the silver resistor tend to fail at.

Also i would not change the silver resistor until it did fail, if you do then any warranty may be void.

Fit the new fan put the car back together and enjoy driving your car
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Old 21st September 2021, 20:46   #8
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We know very little about these latest fans, especially the value of the resistor. I had one in my hands a few weeks back but of course forgot to check for any markings.

I say latest because I’ve noticed these latest ones aren’t the push fit spindle kind I’ve seen in the past but have a screw or bolt in the centre, the fan blade surrounds are very flimsy too: we managed to break it just by holding it while tightening the supplied self-taping screws (not torx). I have some hope that because the original silver resistors have been known to be underrated for a long time, these latest ones might be more robust.

My own car has a silver resistor with a new(ish) fan not more than three years old. I do check the slow speed occasionally and have a gold resistor in the garage drawer in the event it fails.

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Old 22nd September 2021, 06:45   #9
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Quote:
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Hi Simon,
Brushes from Croydon, soldering ok but commutator burnt and concave!!
Hi Malc,

It sounds as if the commutator might be the problem then!

Yes your replacement fan system will run with the silver resistor.

Simon
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