1. Park the truck on a level surface and turn off the engine. Allow it to cool down.
2. Locate the radiator fan clutch. In the Mazda B-4000, it is usually a black plastic housing located between the radiator and the engine.
3. Disconnect the electrical connector for the fan clutch. This is typically a small, two-pin connector.
4. Remove the fan shroud. On some models of the B-4000, the shroud is held in place by a few bolts. On others, it is simply clipped into place and can be removed by carefully prying it off.
5. Remove the fan blade bolts. These bolts are usually located on the back of the fan clutch.
6. Remove the fan blade and fan clutch.
7. Clean the fan blade and fan clutch. Remove any dirt or debris, as it can cause the clutch to slip or overheat.
8. Reinstall the fan blade and fan clutch. Tighten the bolts securely.
9. Reinstall the fan shroud.
10. Reconnect the electrical connector for the fan clutch.
11. Start the engine and test the fan clutch. The fan should turn on and off as needed to maintain the engine's temperature.
Note: If the fan clutch is damaged or does not work properly, it is important to replace it. A defective fan clutch can cause the engine to overheat, which can lead to serious damage.
