Harmonic Balancer

From BMW E34 Encyclopedia

Failure of harmonic balancer will damage all of the accessories including your power steering pump, alternator, water pump, tensioners, and pulleys. A worn or cracked harmonic balancer will create an unnecessary amount of engine vibration.


Start the car and look at harmonic balancer (the big pulley located under the water pump. Your crankshaft position sensor will point directly at the metal teeth of this pulley. If any wobble or shake is emitted, turn off the car and check for 8 bolts holding the harmonic balancer in place. If any of those bolts are missing, replace and repeat procedure.

Damaged harmonic balancer.png



A faulty balancer will cause an excessive load on the V-belt system. You must inspect all of the accessories and at very minimum replace the belt, tensioner, and the pulleys.