Which device is used to absorb torsional vibrations of the crankshaft?

• A. Flywheel
• B. Vibration Damper
• C. Cam Follower
• D. Valve Lash

Answer: (B)

Torsional vibrations come from the crankshaft being hit by uneven firing forces, so engines use a dedicated damper to absorb and dissipate those twisting motions. The vibration damper, often called a harmonic balancer, combines a mass with an elastic (rubber) element to counteract the crankshaft’s twisting at its resonant frequencies, reducing stress and preventing fatigue. The flywheel mainly provides inertia to smooth operation and store energy, not primarily to damp crank torsion. A cam follower is part of the valve train, and valve lash is simply the clearance in the valve mechanism—neither is involved in damping crankshaft torsion.