11 31 090 Removing and installing/replacing chain tensioner piston (N47D20 K/U/O/T 1)

NOTE: To make it easier to remove and install the chain tensioner, it is advisable to arrange the tools (1 to 5).
Connect torque wrench (1) to an extension (2) 1/2 inch with 130 mm and (3) 52 mm.
For better accessibility to the chain tensioner, a swivelable extension (4) with 12° can be used.
Connect nut (5) 24 mm or 27 mm to the swivelling extension (4).

Fig 1: Identifying Torque Wrench And Swivelling Extension

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Release chain tensioner (1).

Tightening torque: 11 12 3AZ .

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 into the clutch housing.

Installation note:

Replace the sealing ring.

Fig 2: 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 support and slowly compress.

Repeat process twice.

Fig 3: Compressing Chain Tensioner

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Installation note:

Install new chain tensioner (1) with AF 24 mm.

Fig 4: Identifying Chain Tensioner

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Assemble engine.