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Viscous fan nut


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I'm trying to replace my water pump on a 3.9 RRC but I'm stalled at the first step....I can't undo the viscous fan nut. There's no belt there to hold the water pump pulley in place so what are my other options? I've seen a suggestion to make a tool that holds 2 of the bolts in place but i don't have facilities to make something like that......

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Firstly make sure you are trying in the correct direction - fans on 3.9s can turn in either direction depending on engine (the serpentine goes the opposite way to the earlier ones) and the nut is always threaded so that the engine torque will be tightening the fan.

Next - your comment re the belt holding the WP pulley while you undo the fan nut - in my experience it won't. The only way I have found is to make the mentioned tool for holding the pulley. All it needs to be is a bit of thin bar ( I use 1" angle) with a hole drilled in it near an end-corner. You bolt through the hole into one of the pulley mounting holes and rest the body of the bar against the spindle.

Hope this helps


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