Deflection/Guide Pulley, v-ribbed belt
Drive Belt Pulley
The drive belt drives the accessories within the engine, such as the water pump, alternator and power steering pump. Like all belts it must be kept tight; a pulley works with the tensioner to ensure this. The dampener dulls down any vibrations caused.
Maintenance is essential and they should be inspected regularly for free play, and wear, and should be changed when the V ribbed drive belt is replaced.