Genuine BMW 11-36-1-403-550 VANOS Diaphragm Spring for M50 M52 S50 S52 Engines

The Genuine BMW 11-36-1-403-550 is a diaphragm spring designed for the single VANOS (Variable Nockenwellen Steuerung) variable valve timing system found in BMW M50, M52, S50, and S52 inline six-cylinder engines. This curved spring plate is a critical component in the camshaft sprocket assembly, installed between the outer stop disks on the intake camshaft.

Function and Purpose:

• Reduces VANOS rattle noise by applying tension to the camshaft sprocket assembly
• Creates resistance to sprocket rotation and dampens rotational play movements
• Presses the stop disks against the sprocket faces while still allowing timing adjustment
• Inhibits splined shaft axial movement within the VANOS mechanism

Key Features:

• Genuine BMW OEM part ensuring exact fit and proper function
• Precision-engineered curved plate design provides optimal spring tension
• Designed to work with BMW part numbers 11-36-1-403-822 (thin outer stop disk) and 11-36-1-403-823 (thick outer stop disk)
• Direct replacement for worn or damaged original diaphragm springs

This diaphragm spring was introduced by BMW in March 1995 as an improvement to reduce rattling in single VANOS systems. It's commonly replaced during VANOS rebuilds or camshaft timing service on compatible BMW models including E34, E36, E39, E38, and Z3 chassis equipped with M50, M52, S50, or S52 engines.