11 31 090 Installing and Removing/Replacing Chain Tensioner Piston (N54)

WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2010 BMW 335xi, 2010 BMW 335i, 2009 BMW 335xi, 2009 BMW 335i, and 2008 BMW 335xi. However, it is still accessible from the selected car via links, so may be relevant.

Release chain tensioner (1).

Tightening torque, see 11 31 5AZ in ENGINE -- TORQUE SPECIFICATIONS -- TWIN TURBO

IMPORTANT: Have a cleaning cloth ready. A small quantity of engine oil will emerge after the screw connection has been released.
Make sure no oil runs onto the belt drive.

Installation:

No sealing ring is fitted during series-production assembly.

A sealing ring must be fitted by service personnel when the chain tensioner is fitted.

Fig 1: Identifying Chain Tensioner

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If the chain tensioner is reused, its oil chamber must be drained. Place chain tensioner on a level working surface and slowly compress.

Repeat procedure twice.

Fig 2: Placing Chain Tensioner

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Assemble engine.