300E radiator fan removal

Hello,
The radiator fan pulley on my '89 300E just split in half so I'm getting ready to replace it but I was wondering if anyone could give me a heads-up
on how best to remove the fan so that I can get to the pulley.
I see that there is a hex bolt in the middle but there also appears to be some slots in the fan hub that indicate the need for a special tool to hold the fan while loosening the bolt. What's the best way to get this off--hopefully without another tool? Do I need to remove the fan shroud?
Also, has anyone else see this pulley fail and if so are there any theories as to why or how?
Many thanks,
Mike
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
You will need this tool to hold the pulley hub. It goes in from the engine side at around 1 o'clock:
http://www.samstagsales.com/SirTool/stm_0040.jpg
It is available here as tool # M0040: http://www.samstagsales.com/mercedes.htm#cooling

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Thank you all for the links to the tools, the home made alternative, and the advice.
Although I think I understand the "spanner like" tool that engages with the back of the hub I'm not clear about the purpose of the "bent pencil" tool. Is it used instead of the spanner or in conjunction and if in conjunction where?
Thanks,
Mike

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I made a tool to remove the radiator fan on my 1987 300E as I did not have the proper Mercedes Benz tool.
Rummaged around in my junk box and found a thick walled metal tube the size of a fat pencil about a foot long that the throttle cable runs through the fan housing on an old VW Beetle. Spent the afternoon filing down the outside of one end until it just fit in the hole in the shaft at the1:00 position mentioned by Karl and Tiger. You will need a flashlight to locate the hole back there. Many test fits including bending an angle in the foot long tube to duplicate the Mercedes tool and allow it to thread down around things to engage the hole.
Probably not worth the effort to save ordering the MB tool, but I am Scottish . . .
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.