11 31 090 Installing and removing/replacing chain tensioner piston (N20, N26)

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Release screws (1).

Tightening torque: 11 65 4AZ .

Fig 1: Identifying Screws

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Raise vacuum unit (1) slightly.

Release chain tensioner (2).

Tightening torque: 11 31 7AZ .

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

Fig 2: Identifying Vacuum Unit And Chain Tensioner

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Installation note:

Replace sealing ring.

If the chain tensioner is reused, its oil chamber must be drained.

Place chain tensioner on a level support and slowly compress.

Repeat process twice.

Fig 3: Installing Chain Tensioner On Level Support

Courtesy of BMW OF NORTH AMERICA, INC.

Assemble engine.