When do I need to replace my Harmonic Damper?
The best indicators that your damper is in need of replacement are when the internal rubber insulator shows wear or if the outer inertia ring of the damper is out of alignment with the hub. Often referred to as a balancer, if the damper is out of alignment/balance, it will work against its intended job of reducing crankshaft vibrations. If the damper exhibits wear, it is simple to find a replacement such as those found on the Professional Products website.
In addition, anyone who is rebuilding an engine should always replace the damper and have it balanced with the rest of the internal engine components. A "balanced" engine, where the crankshaft, rotating assembly, flex plate/flywheel and damper are balanced together is critical to getting the most of your drivetrain. It is amazing how many engine builders skip this critical step when building out an engine, high performance or not. Installing a new damper on a new engine build is cheap insurance against engine vibration and wear.
Harmonic dampers are often referred to as “balancers. But the primary purpose of a harmonic damper is to dampen out the inherent vibrations that occur in any internal combustion engine. Some dampers do serve a secondary purpose on engines that are referred to as “externally balanced.” Due to the difficulty in achieving a true engine balance on certain engines such as a Chevy 400 or all small block Fords, offset weight is added to the damper and the flywheel. Dampers for externally balanced engines serve two purposes; to dampen engine vibrations and to achieve a proper engine balance.
Note: Externally balanced engines are also balanced as an assembly with the damper and flywheel.