Also called OAP, one-way pulley, freewheel pulley.
How you know it is this
- A rattle or chatter from the front of the engine at idle that stops when the engine is revved
- Belt squeal on deceleration
- A belt that keeps failing or fraying
- A pulley that will not freewheel in one direction when spun by hand
Worth knowing before you buy
- It is not a solid pulley. It is a clutch, it is a wear item, and when it seizes it puts shock into the belt and the tensioner.
- Far cheaper than an alternator, and very often the cause of a noise blamed on one.
- Spin it by hand with the belt off: it should turn freely one way and drive the other. If it drives both ways it has seized.
- Needs a special tool to fit, which is worth knowing before starting.
What we need to quote it. The engine code. The chassis number settles the generation, the body and usually the engine in seventeen characters — it is on your mulkiya. A photograph of the old part helps where there is more than one version.
Rest of the starting and charging
Get in touch
Alternator pulley (overrunning) for your Mercedes-Benz?
Send the chassis number and a photograph of the old part. We come back with genuine, OEM and aftermarket options priced side by side, with lead times.
Mon–Sat, 8:00 AM – 6:00 PM · +971 54 303 3119 (Operations Director) · +971 54 241 0599 (Managing Director)