On my 2000 E430 - the original fan clutch seemed to be coming on too often (I had mistakenly bent what I think is the bimetalic strip on the front/center of the OEM clutch).

I replaced the part with a brand new Meyle unit that I ordered from fast lane and now the fan clutch is engaged every time I start the car.

I assumed that the fan clutch engagement was controlled by the unit itself (i.e. there are no wires or other things attached to it).

Do I have a defective unit or have I done something wrong?

__________________
Daily Driver: 02 E430 4MATIC
In the family: '03 E500 // '04 ML500 // 64 220SE

If it's not Sachs @ this point I'd wager you have a Chinese piece... IME, these bits from China never dis-engage, or @ least the few that I got before I realized the Behr units I was getting were made in China and I swapped the all out for Sachs..

Jonathan

__________________
Blue Ridge Mercedes
Jonathan Hodgman
http://www.blueridgemb.com/
Enthusiast Service, Restoration & Tuning.
Follow Us on Facebook!
Located in the Atlanta area
Specializing in all pre and post merger AMG's including Hammers and DOHC M117 engines.
Mercedes Repair Atlanta

The fan clutch engages at startup for 10-15 seconds until the oil inside is distributed correctly. After that, it doesn't start engaging until the engine temp hits about 90C. I have a Meyle and it works fine.

__________________
Prost!

So the engagement at start-up is correct for the Meyle? That seems different from what I recall in the more expensive Sachs.

__________________
Daily Driver: 02 E430 4MATIC
In the family: '03 E500 // '04 ML500 // 64 220SE