1992 500SEL over heating issue.

Hey, i have a 500SEL over heating. I believe the culprit is the fan driven by the engine.

I can literally stop the fan with a stick, possible my hand if i wanted to when its over heating. That's a sign that the fan clutch is gone correct? Does anyone know how this system on the 500sel works? Any experienced replacing it?

Any help much appreciated, Thanks.

A thermomatic fan clutch will engage at a certain temp, a mechanical fan clutch works all the time. The symptoms of a bad fan clutch will cause over heating at highway driving 55MPH+
What happens when you turn the heater on max, during the over heat condition?
Do you got Heat?
No Heat?
Will the temp guage go down?

rev engine to 1500 rpms when hot, if fan does not lock in replace it.

It could be a lot of things. Faulty thermostat, faulty water pump, radiator hoses collapse, viscous clutch defective debris in the radiator ducts clogged radiator, faulty temperature sender motor can not be over-heating, etc. My problem was the viscous clutch.