11 31 090 Installing and removing/replacing chain tensioner piston (N52)

Release chain tensioner (1).

Tightening torque 11 31 4AZ .

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

Installation:

No sealing ring is fitted during series assembly.

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

Fig 1: Identifying Chain Tensioner

Courtesy of BMW OF NORTH AMERICA, INC.

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: Draining Oil Chamber Of Chain Tensioner

Courtesy of BMW OF NORTH AMERICA, INC.

Assemble engine.