What is a pulley?
A pulley is often referred to as an alternator pulley, an Overrunning Alternator Pulley (OAP), or a freewheel pulley. A pulley is the link between the alternator and the engine output crankshaft pulley.
What does a pulley do?
Pulleys transfer power. In a car, pulleys transfer engine power to devices such as the alternator, the power steering module and the air conditioning compressor. They are a crucial part of correctly functioning engine system.
Alternator pulleys are also used to:
- Provide protection to the belt drive system by filtering out vibration from the engine, increasing belt drive lifespan
- Reduce noise, vibration and harshness (NVH) from the belt drive, for increased driver comfort
- Reduce friction loss as a result of belt slippage
- Enable the alternator rotor to operate in freewheel mode when the engine is slowing down or stopped, helping save fuel and reducing CO2 emissions
Valeo: Original Equipment pulley suppliers
One in three cars in Europe are fitted with Valeo pulleys as Original Equipment (O.E.) and Valeo brings that experience and expertise to the aftermarket. To ensure O.E. quality, Valeo pulleys are tested for a series of quality benchmarks, such as:
- Salt spray test
- High-pressure sealing
- Load bearing resistance
- Large temperature differentials
- Cycle speeds
- High number of stops and starts
Valeo currently offers more than 100 part numbers dedicated to 14,000 vehicle applications worldwide. Trust Valeo for all your pulley needs.