Engine cooling fan/clutch

[Lori H]

Anyone know what the scoop is with our factory Mopar cooling fans?  I've heard viscous and clutch driven.  Are they the same?  Whatever the case, is there a test to verify that they engage properly?  We are removing the radiator and would like to test the operation of the fan.

Our last trip was teetering on a boil-over while driving from Ellensburg to Yakima, WA.  Just when you thought you made it over the pass and heading down hill...here comes another.  And another.  Talk about an emotional rollercoaster!

[Shayne]

They use a viscous clutch.  With the motor OFF, you should be able to turn the fan by hand without much effort and without making belts slip.  As that clutch wears out, it gets to the point wear it won't engage when it should and you can get overheating.

Some just replace with another clutch while others go to direct drive fans.  Direct drive fans can rob some power as they are always pulling air and can rob some power if you don't actually need the fan pulling.. like in cooler weather or flat ground.  But you always know they're pulling air.