The crankshaft pulley assembly for the accessory drive system mounts on the torsional damper, using four bolts (refer to Figure 5-3). The pulley assembly has an inner hub (fastened to the crankshaft) and an outer pulley (connected to the inner hub with vulcanized rubber and ball bearing).
The ball bearing and rubber mounting allow the outer pulley to rotate slightly in relation to the inner hub. This occurs briefly when changes in crankshaft speed during acceleration and deceleration vary slightly with the rotating speed of the drive belt and its accessory loads.
