Over the weekend I was working on my 87 300td and noticed the cooling fan continued to spin for a bunch of revolutions after the ignition was turned off. The car was not up to operating temp. Is this a sign of a bad fan clutch or does the water temp have to be at an elevated temp in order for the clutch to kick in?

Thanks.

Generally the fan clutch and fan should stop spinning not long after the engine is stopped. Look for oil staining around the fan clutch. That indicated that the fluid inside the clutch is leaking out and the clutch won't work as well. I personally have never heard one "cut in". My Dodge-Cummins powered will cut in when the temp goes up. I replaced the fan clutch on my wifes old '84 300D wagon with a new German one and I neve heard it cut in even when the temp was up. It didn't ever over heat.

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My Truck.. 2007 DODGE, 5.9 Cummins, 6spd stick, 4X4. My car..1977 240D, OTHER WHEELS...1955 VW Oval window bug, European Delivery (Holland) with a 1700cc, 2 barrel, Porsche drum brakes. 1939 WILLYS Pick-up. 1967 Triumph 200cc Tiger Cub. 1976 Honda 550F 4cyl Motor Cycle.

You should not have that much "coasting" whether the fan is cold or hot. Replace it.