G4 Alternator Belt Relay Roller - 1.4-1.6

This deflection (guide) pulley is a critical part of the auxiliary drive system on Volkswagen petrol engines fitted with air conditioning. Its job is to guide and stabilise the v-ribbed (serpentine) belt as it runs around the crankshaft, alternator, power steering pump, and air conditioning compressor. By maintaining the correct belt path and wrap angle, the pulley helps prevent belt slip, noise, and uneven wear.

The pulley rotates on a sealed bearing and is mounted to the engine bracket, allowing the belt to run smoothly under constant load. Over time, heat, dirt, and bearing wear can cause the pulley to become noisy or seize, which can quickly destroy the auxiliary belt. Replacing a worn guide pulley restores quiet operation and protects the belt and driven components.

This pulley is designed specifically for vehicles with air conditioning, where belt routing and loading differ from non-AC systems. It matches original dimensions for correct alignment and long service life.

Technical details

• Belt type: V-ribbed / auxiliary belt

• Vehicle equipment: For models with air conditioning

• Outer diameter: 76 mm

• Width: 26 mm

• Inner diameter: 17 mm

Related parts to consider

• V-ribbed auxiliary belt (correct length for AC models)

• Auxiliary belt tensioner (if fitted separately)

• Tensioner pulley (if part of the same belt run)

Vehicle Fitment Summary

Volkswagen Bora

• 1.4 Petrol 75 PS: 2000–2005 (Saloon & Estate)

• 1.6 Petrol 105 PS: 2000–2005 (Saloon & Estate)

• 1.6 Petrol 110 PS: 2002–2005 (Saloon & Estate)

Volkswagen Golf IV

• 1.4 Petrol 75 PS: 1997–2004 (Hatchback), 1999–2006 (Estate)

• 1.6 Petrol 105 PS: 2000–2006 (Hatchback & Estate)

• 1.6 Petrol 110 PS: 2002–2006 (Hatchback & Estate)

Petrol models with air conditioning only.