Parts Catalog Accessories Catalog Tech Info Tech Forums
  Search our site:    
 Cart  | Project List | Order Status | Help    

Go Back   PeachParts Mercedes ShopForum > Technical Information and Support > Tech Help

LinkBack Thread Tools Display Modes
Old 07-25-2000, 11:56 PM
Registered User
Join Date: Apr 2000
Posts: 117
With so many messages lately that involve questions about the radiator fan clutch slipping, I'd like to know HOW to judge how much slippage is normal -- or, how much is too much.
My concern is that all of my cars (see list below) appear to have about the same amount of "slip" when hot or cold -- they don't seem different when fully warmed up.
To test them, I reach in and give the fan blade a fast, strong push, and the blade spins a bit -- usually, the blade tip can be moved about 1 to 2" before it abruptly stops. No matter how hard you try, they never spin more than that, but it's the same hot or cold. Admittedly, my W124's blades seem to most resistance to spinning (they only move about an inch), but none of them seem any "looser" when cold than when hot.
Thus, I wonder -- if they're supposed to have more slippage when cold (or less when hot), is that little bit of slip that I find when hot (identical to cold) too much? I can't imagine them being much tighter, unless (when hot) they're not supposed to be able to turn at all -- is that the case? Then, all my clutches would seem bad. I'd appreciate your advice.
In advance, thanks.
[my cars: '84 W463/M110; '88 W201/M102; '88 W124/M103; and '90 W124/M103]
Reply With Quote
Old 07-26-2000, 12:17 AM
Registered User
Join Date: Jun 1999
Location: Los Angeles, Calif, USA
Posts: 521
I can never tell the fan clutch condition by pushing the fan blades, unless it is very bad. I test my cars (300D and 300SD) by increasing the engine rpm when it is cold and hot (~95 degree, necessary) and listen to the fan noise. I posted detail steps in the past. Search this forum to see if you can find them.


PS: The fan clutch works a little more complicated (or smarter) than you think. I am not smart enough to tell if it is bad by pushing fan.

[This message has been edited by be459 (edited 07-26-2000).]
Reply With Quote
Old 07-26-2000, 12:39 AM
Registered User
Join Date: Jan 2000
Location: New Bedford, MA USA
Posts: 1,583
Ken, It is difficult to judge viscous clutch operation with the engine not running. The viscous clutch depends in part on centrifugal force to distribute the silicone inside the clutch housing. Check David's posts and follow his advice. If your's are OK, you should be hearing them come on line at between 90 and 95 centigrade.

Jeff Lawrence
1987 300e
1989 300e
2000 Dodge Grand Caravan SE
Reply With Quote
Old 07-26-2000, 10:58 AM
yal's Avatar
yal yal is offline
Join Date: Oct 1999
Location: New York, Long Island
Posts: 2,704
The M102 engine has an electro magnectic fan. This fan free wheels just like a clutch fan but engages electrically from a thermo switch on top of the engine block. It is often mistaken for a viscous clutch system except it does not gradually get stiffer it just cuts in (100 C)and then cuts out.

88 230E (W124) M102

[This message has been edited by yal (edited 07-26-2000).]
Reply With Quote


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
replaced fan clutch - is new clutch defective? janko Tech Help 13 07-08-2005 01:05 PM
DIY Notes may help people: Radiator, Fan Clutch, Temp Sensors, Fuel Pump, Temp Gauge ericgr SL Forum 3 09-24-2004 01:40 AM
Any reason to leave a fan with a dead clutch installed? The Warden Diesel Discussion 17 12-22-2003 07:28 AM
Auxiliary Fan Question JBoggs Tech Help 9 07-30-2003 10:07 PM
190e fan clutch benzoso Tech Help 1 03-30-2002 07:06 PM

All times are GMT -4. The time now is 07:44 PM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2016, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2011 Pelican Parts - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page