Crankshaft Pulley

The crankshaft pulley (harmonic balancer) is mounted on the end of the crankshaft. Its purpose is to turn the drive belts that operate the engine accessories (alternator, air conditioning compressor, etc.)

Symptoms of a Bad or Failing Crankshaft Pulley

  • Knocking noise
  • Engine accessories may stop working
  • The crankshaft bolt securing the pulley can loosen, affecting operation of the pulley
  • The harmonic balancer includes a rubber insert between the center portion of the crankshaft pulley and the outer surface; this is what drives the belts
  • The rubber insert can become damaged, resulting in an abnormal noise. The outer surface can also "slip" on the rubber insert, which can affect the ability to set the ignition time on older engines

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