Check the rubber between the inner and outer rings. Any cracks show that the rubber is hardened up, which would be 99% expected at this age of part. The hardness of the rubber is part of the tuning of the damper to properly damp out a critical frequency range of internal crankshaft vibrations; when it gets hard, it does not do its job well (or maybe even at all).
The damper's job is to damp out high frequency internal vibrations within the crank itself (which have nothing to do with imbalance vibrations). Inadequate damping of these internal vibrations can sometimes lead to premature crank failure. That is the whole point of using one.