On the Ford 300 six-cylinder engine, the fan clutch nut is screwed onto the water pump by a large retaining nut, which requires a special tool to remove. This tool holds the water pump pulley and turns the nut at the same time. The fan clutch tool looks like a large wrench on one end and is available at all auto supply stores. The threads of the fan clutch nut are the reverse of the way nuts usually loosen. The fan clutch nut turns to the right to loosen it and to the left to tighten it.
Remove the fan clutch tool from the package. One piece of the tool locks onto the pump pulley bolts. The other fits snugly on the fan clutch nut.
Place the larger end of the tool onto the face of the water pump pulley between the bolts on the back sides. Fit it as if you were putting a wrench on a bolt.
Place the other tool on the fan clutch nut and hold it in place. Grasp both tools firmly and loosen the nut on the fan clutch by turning it clockwise. Continue loosening it until the nut separates from the water pump.
