Nissan Repair: Nissan 2.7 Diesel Hardbody Pick up

Question
How do you test if the radiator viscous/clutch fan is working properly. How do you remove it, as it appears to be heat fitted to the water pump shaft, and as it is made of aluminium I don't want to hit it with a hammer. Once it's off can I clamp it so that it always runs, or do I have to replace it? Thank you

Answer
Hi Dick -

The fan clutch system is designed to tighten up as the temperature gets higher to control load on the engine. The older models used silicone and you could refill it as needed by taking off a screw on the clutch and loading it with silicone.

The newer models you will have to replace the entire clutch.

Although there is no scientific way to test the clutch, you can tell if it needs replacement by the speed in which it is turning the fan at engine operating temp.

Some people have welded it together in order to get more cooling. This is fine, however you will have to devise a way to lock it without disturbing the balance of the fan, otherwise you will get excessive vibrations and early demise of the water pump. So a clamp may not work. You may try epoxying the joint if welding is not an option.

Hope this helps and answers you questions -
aloha
Calvin