A heavy, rubber-damped pulley that bolts to the snout of the crankshaft and drives the accessory belts. It acts as a torsional damper, absorbing the destructive twisting forces created by each cylinder firing. Without it, the crankshaft could eventually fracture from the harmonic resonance.
You'll need a specialized puller to get that harmonic balancer off the crank snout.
The rubber ring separating the inner hub from the outer heavy ring can dry rot and slip, throwing off the ignition timing marks.
Also heard as
- torsional damper
- crank pulley
Related terms
Bottom-end
The lower section of an engine block containing the crankshaft, connecting rods, and main bearings.
Crankwalk
Excessive axial play in an engine crankshaft that allows it to shift back and forth.
Timing belt
A reinforced rubber belt that synchronizes the rotation of the crankshaft and the camshafts.