The fan clutch on your Chevy helps the cooling fan blow air through the radiator and over the engine, thus helping the water pump and radiator to control engine temperature. However, a worn out or damaged clutch may lock and cause the engine to overheat if the fan fails to operate or operates below the required temperature if the clutch locks in the "On" position. To replace the fan clutch, you will need a couple of special tools. Before you begin, make sure you have the right set of tools for your particular Chevy model.
Park your Chevy vehicle on a level surface.
Open the hood and remove the upper fan shroud using a ratchet, ratchet extension and socket.
Install special tool J-41240-1 or a similar clutch-holding tool into the water pump access holes. This will prevent the clutch from turning as you release the fan clutch nut.
Install special tool J-41240-2 or similar fan clutch hub wrench on the fan clutch nut. Then insert a breaker bar on the special tool square hole.
Hold the water pump firmly with the holding tool as you turn the fan clutch nut counterclockwise. With the clutch nut loose, spin the clutch free by hand the rest of the way.
Remove the fan and clutch assembly from the vehicle.
Set the fan/clutch assembly on a workbench with the fans facing down and unscrew the fan from the clutch using a wrench.
Fasten the fan to the new clutch using the wrench.
Set the fan/clutch assembly in place and start the fan clutch nut by hand. Make sure to align the yellow mark on the fan clutch hub with the yellow paint mark on the water pump hub if these components are marked. This is necessary to maintain the assembly balance during operation.
Hold the water pump with the special holding tool and use special tool J-41240-2 or similar fan clutch hub wrench to tighten the fan clutch nut.
Remove the tools from the engine compartment.
Install the upper fan shroud using the ratchet, ratchet extension and socket.
