Today I had a Holden Commodore broken down in Surfers Paradise. This time the cause was a failed harmonic balancer. The Harmonic balancer is bolted to the front of the crank shaft to dampen engine vibration and act as the main pulley for the drive belts. As the balancer is made of rubber it can wear out and fail. This engine was making a large ‘knocking’ noise when running which was from this failed harmonic balancer.
The balancer needs to be replaced when its worn out as it not a part that can be refurbished or repaired. On the Commodore this is a relatively easy job with the correct tools and knowledge.
You can see the failed balancer in the main pic and the comparison in the pic below.