Find the right replacement for your viscous fan drive
Fan Diameter
Measure across your fan.
Fan Rotation
Place your fan engine side down on the floor/counter. Look at the blade that is in the 12 o'clock position. One side of the blade will be resting on the floor and one side will be raised.
• If the Right side is raised, then your fan is Clockwise.
• If the Left side is raised, then your fan is CounterClockwise.
Mount Type
Is your fan clutch mounted with a spin-on bracket, or with a bolt-on, flanged bracket?
Length
Measure from the base of the studs to the back of the bracket.
Fan Pilot
Measure the fan pilot. This can also be measured on the fan.
Fan Bolt Circle
Measure from the center of one stud or bolt hole to the center of the opposite stud or bolt hole.
Drive Pilot
Measure the inside diameter of your drive pilot on the back of the mounting flange. Some may have a male pilot that sticks out. In this case, measure the outside diameter of the drive pilot.
Drive Bolt Circle
Measure from the center of one bolt hole to the center of the hole on the opposite side of the bolt circle.
Thread Type
Length
Measure from the base of the studs to the back of the bracket.
Fan Pilot
Measure the fan pilot. This can also be measured on the fan.
Fan Bolt Circle
Measure from the center of one stud or bolt hole to the center of the opposite stud or bolt hole.