Enhanced fan and fan drive assembly

A fan drive assembly of the type comprising a cooling fan attached to a fluid coupling device, said cooling fan comprising a fan hub, a spider portion and a plurality of fan blades extending radially from said fan hub;

• said fluid coupling device comprising a rotatable coupling member disposed in said fluid chamber for rotation relative to said coupling assembly;
• said coupling assembly and said coupling member cooperating to define a viscous shear chamber therebetween, whereby torque may be transmitted from said coupling member to said coupling assembly in response to the presence of viscous fluid in said viscous shear chamber;
• said body member including a plurality of cooling fins and a plurality of mounting portions, said spider portion being attached to said mounting portions and defining a pilot diameter;
• characterized by:
• (a) each of said plurality of mounting portions being disposed immediately adjacent an outer periphery of said body member;
• (b) each of said mounting portions defining a machining chucking surface, and a spider mounting surface on a rearward face thereof, said spider mounting surface including a radially disposed pilot surface in engagement with said pilot diameter of said spider portion;
• and
• (c) said plurality of cooling fins covering substantially all of said rearward surface of said body member not covered by said mounting portions.