a decoupler assembly with a torsional damping system and a torque limiter . the torsional damping system has a torsion spring that facilitates transfer of rotary power into a hub . the torque limiter is wrapped about the torsion spring and radially expands with the torsion spring as a magnitude of the rotary power transmitted through the torsion spring increases . contact between the torque limiter and another structure in the decoupler assembly halts radial expansion of the torsion spring .