Cooling; Removing engine driven radiator fan

For all your questions, problems and DIY stories
Aus323i
Upcoming E21 fanatic
Posts: 47
Joined: Wed Jan 09, 2013 3:00 am
My E21(s): 1981 EU 323i Auto
Location: Sydney, Australia

Cooling; Removing engine driven radiator fan

Post by Aus323i »

Hey everyone,
Small problem. I've been trying to remove the engine-driven fan and have talked to people at a BM garage where they told me to use a 32mm (not sure what that is in imperial) to undo the bolt at the back of the fan. Reverse thread.

I've also seen somewhere that you are meant to undo 4 bolts on the reverse side of the fan which holds the fan mechanism together

Image

Anyone have a solution to this? Its a bit of an amateur problem and don't 100% know how to word everything but I've got to find out somehow haha

Regards,
Max


User avatar
Thegs
E21 VIP
E21 VIP
Posts: 2419
Joined: Tue Feb 13, 2007 7:05 pm
My E21(s): '78 320/6 4-sp
'80 323i 5-sp
Location: Wezep (Gld, The Netherlands)
Contact:

Re: Cooling; Removing engine driven radiator fan

Post by Thegs »

Yes, you need to use a 32mm spanner to undo the fan and yes it is reverse thread! But you need to block the fan, because else it will be slipping on the fanbelt. Some suppliers will provide tools to block the pully of the waterpump, but you propably can make it yourself. It can be a pain to remove when it is on there for some years :bag
Regards, Gerwin

1980 BMW E21 323i in Hennarot
1985 BMW E23 735i EXE in Zobelbraun
1988 BMW E34 535iA in Lachssilber
2004 BMW E53 X5 4.8iS in LeMansblau
2007 Mini R56 Cooper in Chilired
User avatar
Jeroen
Site Admin
Posts: 29994
Joined: Tue Sep 14, 2004 12:23 pm
My E21(s): '81 323i Baur
Location: The Netherlands
Contact:

Re: Cooling; Removing engine driven radiator fan

Post by Jeroen »

If you undo the 4 pcs 10mm head bolts the fan pulley will come loose, but it won't get you anywhere as the fan isn't on the pulley. There are tools that can be fitted using two of these bolts so you can stop the water pump from moving when you try to undo the 32mm fan bolt, basically a long piece of flat metal with two holes in it that you can easily make yourself.

But most times I'm able to undo the large nut without this 'tool'.

Stand on the left hand side of the engine bay (fusebox side)
Make sure the fan belt is under enough tension
Place the 32mm spanner, best is to have it point slightly to the right (away from you)
Put on workman's gloves or whatever they're called
With your right hand, push the fan belt down go obtain extra tension (usually I use a short piece of a 2x3", that's safer)
With the extra tension on to prevent rotation, use your left hand to pull the spanner towards you in one strong pull

Especially with M20's with the 32mm nut, for me this does the job 90% of the time.
Regards/groeten, Jeroen
Aus323i
Upcoming E21 fanatic
Posts: 47
Joined: Wed Jan 09, 2013 3:00 am
My E21(s): 1981 EU 323i Auto
Location: Sydney, Australia

Re: Cooling; Removing engine driven radiator fan

Post by Aus323i »

Thanks, for the quick reply both of you. I'll go down and give that a try right now.

I'll be back with the results soon

Cheers,
Max
User avatar
nas80
E21 Mad
Posts: 2975
Joined: Sun Jun 14, 2009 12:12 am
Location: West Yorkshire

Re: Cooling; Removing engine driven radiator fan

Post by nas80 »

I Always smack the nut with a chisel so it is going clock wise. A couple of swift taps always gets it off with minimum fuss.
[img]http://s13.photobucket.com/albums/a285/nasbucket/forumsig.jpg[/img]
User avatar
Jeroen
Site Admin
Posts: 29994
Joined: Tue Sep 14, 2004 12:23 pm
My E21(s): '81 323i Baur
Location: The Netherlands
Contact:

Re: Cooling; Removing engine driven radiator fan

Post by Jeroen »

Never tried that one, but in some cases I just hit the spanner with a hammer, especially if there's no room for other solutions like with the later 6 cil engines M52-M52 etc. Since you don't hit the water pump on the head but in its normal direction I think you're less likely to do any damage to the water pump.

Just be careful not to hit anything else... I just broke the fan shroud on my girlfriends car. Only hit the shroud slightly but in the cold that's enough to break it :roll:
Regards/groeten, Jeroen
Aus323i
Upcoming E21 fanatic
Posts: 47
Joined: Wed Jan 09, 2013 3:00 am
My E21(s): 1981 EU 323i Auto
Location: Sydney, Australia

Re: Cooling; Removing engine driven radiator fan

Post by Aus323i »

Thanks Jeroen for the help,
I have been very unsuccessful though.
I cannot seem to put enough pressure on the fan belt to stop the water pump from moving. Yet, the band
So I do think that some fabrication is in need to create myself this tool..
It just cant seem go the easy way haha
cobbler2u
E21 Pro
Posts: 843
Joined: Fri Apr 17, 2009 8:17 pm
My E21(s): 323i baur
323i special
328 sport
325i
Location: hertfordshire

Re: Cooling; Removing engine driven radiator fan

Post by cobbler2u »

Id go with what nas said. Give it a few wacks its the easiest way
User avatar
e21-Mark
E21 Master
Posts: 5715
Joined: Fri Mar 21, 2008 2:19 pm
My E21(s): 316 m52/2.8 Cat Cams & Jenvey ITB
Facebook page: https://www.facebook.com/JackyardBackoff
Location: Cornwall - UK

Re: Cooling; Removing engine driven radiator fan

Post by e21-Mark »

Try and borrow an impact gun.
Aus323i
Upcoming E21 fanatic
Posts: 47
Joined: Wed Jan 09, 2013 3:00 am
My E21(s): 1981 EU 323i Auto
Location: Sydney, Australia

Re: Cooling; Removing engine driven radiator fan

Post by Aus323i »

I'll go give that a try before making this tool then,
The previous owner had a go at making this tool and I have his attempt but the holes he drilled to hold the two bolts in are no where near big enough
Right, time to go give it a smack. I'll be back with how I went soon haha
User avatar
Jeroen
Site Admin
Posts: 29994
Joined: Tue Sep 14, 2004 12:23 pm
My E21(s): '81 323i Baur
Location: The Netherlands
Contact:

Re: Cooling; Removing engine driven radiator fan

Post by Jeroen »

There are two approaches for this tool, one is to remove two bolts and put them back in with the tool fitted, this is the safe way. There are also tools that just go over the heads of the bolts but in that way it is easy to damage the heads and the tool can come off easily as well, too.
Regards/groeten, Jeroen
User avatar
nas80
E21 Mad
Posts: 2975
Joined: Sun Jun 14, 2009 12:12 am
Location: West Yorkshire

Re: Cooling; Removing engine driven radiator fan

Post by nas80 »

You just need a long-ish cold chisel and a hammer. Remember its reverse thread. Bang the edge of the nut clockwise and it'll just free itself.
[img]http://s13.photobucket.com/albums/a285/nasbucket/forumsig.jpg[/img]
pampa
Newbee
Posts: 7
Joined: Mon Jan 07, 2013 3:01 am
My E21(s): 1982 E21 323i 5spd .1967 Triumph TR4a
Location: Wagga Wagga.N.S.W.Australia

Re: Cooling; Removing engine driven radiator fan

Post by pampa »

I got mine off with a length of flat steel with hole drilled in end corner,bolted to one of the small pully bolts then give 32mm spanner a big whack with a hammer(make that a lot of whacks) and it finally came loose.
trash-berd
Upcoming E21 fanatic
Posts: 66
Joined: Wed Mar 06, 2013 3:15 am
My E21(s): '82 320i US Manual 1.8L
Facebook page: https://www.facebook.com/eli.tripi.5
Location: Renton WA - US

Re: Cooling; Removing engine driven radiator fan

Post by trash-berd »

What if said bolt doesn't seem to exist?

Image
Aus323i
Upcoming E21 fanatic
Posts: 47
Joined: Wed Jan 09, 2013 3:00 am
My E21(s): 1981 EU 323i Auto
Location: Sydney, Australia

Re: Cooling; Removing engine driven radiator fan

Post by Aus323i »

I can't help you there, sorry.

But for those that do have a nut

http://www.ebay.com.au/itm/BMW-32mm-Fan ... 9b9&_uhb=1

There is a tool specifically designed for it. I wasn't able to fabricate one and I just needed to get it off.
Great quality and good shipping time

Max
Post Reply