Drive belt deflection roller. Porsche 996 / Boxster 987 / Cayman 987C / 997

Drive belt deflection roller.
A direct-fit idler/deflection pulley for the auxiliary (serpentine) drive belt. Built to OE geometry, it guides the belt path, stabilises belt tracking, and helps maintain correct wrap on the alternator, A/C compressor and power-steering/water pump pulleys.

Fits:
Porsche 996 Carrera 3.4L / 3.6L 1997-05 6-speed Manual transmission
Porsche 997.1 Carrera 3.6L / 3.8L 2005-08 Manual transmission
Porsche 987.1 Boxster 2.7L / 3.2L / 3.4L 2005-08 Manual transmission
Porsche 987C.1 Cayman 2.7L / 3.4L 2005-08 Manual transmission

Diagram ref No 12

The deflection roller maintains smooth, stable tension in the auxiliary belt system. It helps guide the belt precisely over pulleys, reduces vibration, and ensures efficient power delivery to engine accessories such as the alternator, A/C compressor, and power steering pump. Built with OE-spec bearings, it delivers quiet operation and long-lasting reliability under high-speed, high-load conditions.

Over time, the bearing inside the roller can wear, dry out, or seize due to constant load and heat exposure. A failing roller may cause belt noise, vibration, or premature belt wear, potentially leading to accessory drive failure.

Replace the deflection roller when:
• You hear squeaking, chirping, or grinding from the belt area
• The pulley feels rough or loose when rotated by hand
• During belt or tensioner replacement as preventive maintenance
• There are signs of belt misalignment or edge fraying

Installing a new deflection roller ensures correct belt tracking, quiet performance, and dependable accessory drive operation.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

99710211900

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