W123 radiator fan issue
 

Hey folks,

There's an issue with my radiator fan on my 1984 230e. It doesn't spin properly - it spins very slowly and has no resistance (you can stop it easily with your fingers without losing any of them!)

The problem is actually exactly like this video I found on Youtube (a few seconds long): https://www.youtube.com/watch?v=XQAGmxPY8LQ

I guess a clip or something is broken somewhere? Any ideas how to fix it?

Thanks :)

Don't put your hand in there even if you can stop it with your fingers.....if it suddenly catches and begins working you're in trouble. If those run on a magnetic clutch I would start there to make sure it engages.

You either have a bad electromagnetic fan clutch or a bad switch that signals it to engage.

Ah ha, thanks! Any tricks for figuring out which/sorting it out?

I'm not too familiar with that model, but I'm assuming the clutch must be similar as the electromagnetic clutch on my a/c compressor. Have the car off and apply 12v to it to hear if it engages. If it's not that type of clutch and it's temp controlled, try applying heat to it to see if it will engage. If not, replace the clutch. Anyone else have anything to add?

Where is the switch for the fan located? :)

You should have two thermo switches at the front of the motor next to the air filter housing. One is for the temp gauge, the other for the fan. The early 230s have a single pole while the later ones have a double. You can jump the double while connected or just ground the single. But you have to make sure the clutch has its power source. The best way to make sure is to simply power and ground the clutch directly at its terminal.