Engine parts specialist BGA has highlighted the important role that the Over Running Alternator Pulley has in regulating vehicle performance and how quality is vital when it comes to these crucial components. 

OAPs operate in an extreme environment and are subject to extreme input changes. The pulley’s sole job is to absorb these operating speed changes and vibrations. This then protects the rotating electrics of the alternator, providing longer life and better performance by allowing them to rotate smoothly and consistently, whilst reducing belt noise. 

BGA says its engineers understand the mechanical and physical performance properties a quality OAP requires. They extensively test in house, on custom made real life road simulation stress test machinery against the original part. To ensure optimum performance, they only install the highest quality performance needle roller bearings and pinch rollers to ensure the BGA OAP will match or surpass OE quality.

As well as focusing on the bearings the engineers also analyse the construction and fit, utilising CMM and shadowgraph analysis of the bodies to ensure consistent fit and function. The OAPs are also galvanised to give additional protection from corrosion. Each unit is also fitted with a plastic sealing cap that prevents contamination of the bearings, extending the life of the pulley.

BGA engineers say that signs of an OAP failure can include; unusual drive belt noises, the alternator failing to charge, unusual vehicle vibrations and the Pulley spinning in both directions. If a technician spots these symptoms then the pulley should be checked and replaced where required.