A viscous clutch assembly includes a rotationally fixed center shaft, a rotor rotatably supported on the center shaft, a housing rotatably supported on the center shaft, a working chamber, a reservoir carried by the rotor, an electromagnetic coil located at or near a front end of the center shaft, a valve subassembly magnetically operable to control flow of a shear fluid between the reservoir and the working chamber, a flux guide extending axially across a cover of the housing, and a magnetic flux insulating material positioned adjacent to and radially inward from the flux guide. A flux circuit located forward of the rotor connects the electromagnetic coil and the valve subassembly and passes through the flux guide and the center shaft, with the magnetic flux insulating material at least partially surrounded by the flux circuit.