1995 190E fan clutch
 

My grandpa has a 190E 2.6

The fan doesnt spin and the aux electric fan in front spins in city driving. My suspision was the fan clutch. My grandpa bought the clutch at the MB dealer in SF and took it to some local shop. Now the fan spins very slowly and can be stopped if you hold it.

Dont know what else to try:confused:

The fan on your car has a viscous coupling and won't lock up until the engine is at operating temp, when cold the fan can be turned freely.
See here for a full explanation ;http://mb.braingears.com/124_DISC1/Program/Engine/602_603/20-310.pdf.