Pelican Parts
Mercedes-Benz Parts Catalog Accessories Catalog Mercedes-Benz How To Articles Mercedes-Benz Tech Forums
Call Pelican Parts at 888-280-7799
View Recent Cars  |Shopping Cart Cart | Project List | Order Status | Help
 >  >
Removing Your Fan on your Mercedes-Benz
 
Bookmark and Share

Pelican Technical Article:

Removing Your Fan on your Mercedes-Benz

Steve Vernon

Time:

1 hour1 hr

Tab:

$45

Talent:

**

Tools:

10mm socket, Flathead screwdriver

Applicable Models:

Mercedes-Benz W126 (1981-91)

Parts Required:

Fan

Hot Tip:

Work on a cold engine

Performance Gain:

Engine runs at the proper temperature

Complementary Modification:

Replace older hoses

The Viscofan in the Mercedes-Benz W126 has an important job in keeping the engine cool. As the hot air coming through the radiator reaches certain temperatures it causes the bimetallic strip on the front of the fan to change shape and allows the oil in the clutch to circulate and turn the fan. This allows the fan to move with the engine speed up to 3800 RPMs. If the Viscofan is not working correctly then the fan will either not cool correctly or spin at high RPM when not needed. Either way it is not working correctly and needs to be fixed.

You can easily remove the Viscofan while radiator and shroud are still in the engine bay.

There are four 10mm bolts holding the back of the Viscofan to the front of the cooling pump. You do not need to remove any of the drive belts to replace the fan. You need to hold the fan in place while unscrewing the four 10mm bolts, and while there are lots of different tools made to do this I just place a large screw driver between the fan center and one of the bolts. They are not held on under a lot of torque and should easily come off. Do NOT attempt to place anything between the fan blades to keep it from turning as you can easily damage the fan and yourself.

With the Viscofan out of the engine bay you can undo the four 10mm bolts holding the fan to the clutch assembly and replace the clutch.

Installation is the reverse of removal.

There are four 10mm bolts holding the back of the Viscofan to the front of the cooling pump (green arrow).
Figure 1

There are four 10mm bolts holding the back of the Viscofan to the front of the cooling pump (green arrow). You do not need to remove any of the drive belts (red arrows) to replace the fan. You need to hold the fan in place while unscrewing the four 10mm bolts, and while there are lots of different tools made to do this I just place a large screw driver between the fan center shaft and one of the bolts. The bolts are not held on under a lot of torque and should easily come off. Do NOT attempt to place anything between the fan blades to keep it from turning as you can easily damage the fan and yourself.

With the Viscofan out of the engine bay you can undo the four 10mm bolts (yellow arrows) holding the fan to the clutch assembly and replace the clutch.
Figure 2

With the Viscofan out of the engine bay you can undo the four 10mm bolts (yellow arrows) holding the fan to the clutch assembly and replace the clutch.

Bookmark and Share
Comments and Suggestions:
350sdlvr Comments: The 8mm Allen bolt Bruce is referring to is in the center of the fan. You will need a long handle 8mm "L" Allen wrench or a T 50 tourqes order to loosen the bolt. Also it would be helpful to have a pulley tool on hand. Once the Allen bolt is loosened you can turn the water pump pulley as you hold the bolt for removal.
February 25, 2017
  Followup from the Pelican Staff: Thanks for the help! We appreciate your contribution to the DIY community.. - Casey at Pelican Parts  
Ken Comments: How do you do the same R&R on a 1990 300 SE?
June 19, 2014
  Followup from the Pelican Staff: Check here to see if your vehicle is lested here:
http://www.peachparts.com /Wikka/DoItYourSelf - Nick at Pelican Parts
 
Bruce Comments: what about the 8mm allen bolt holding on the clutch to the pully? mine is 1988 w126 perhaps they made it easier
August 31, 2013
  Followup from the Pelican Staff: The procedure for vehicle should be the same. I am not sure what Allen bolt you are referring to. - Nick at Pelican Parts  
Bert Comments: Particularly helpful was using the large screwdriver, as you suggested, to keep the fan pulley from slipping on the belts as the four bolts were removed. Worked like a charm!
August 19, 2013
  Followup from the Pelican Staff: Thanks for the follow up. We appreciate it. - Nick at Pelican Parts  
Bert Comments: Thanks for this information!
August 18, 2013
  Followup from the Pelican Staff: Thanks for the feedback. Glad we could help. - Nick at Pelican Parts  

QUICK LINKS
About Us
Careers
Pelican Parts, Inc.
1600 240th Street
Harbor City, CA 90710
Order Online or Call:
888-280-7799
CONNECT WITH US
NEWSLETTER
Sign Up for Pelican Pit Stop News & Special Offers
Page last updated: Fri 5/26/2017 02:29:00 AM