Overview - Camshaft Timing Chain, Engine With Two Camshaft Adjusters

• After removing or replacing the chain drive components the adaptation values for the chain length must be adapted again. Use the Vehicle Diagnostic Tester 01 - Engine electronics, functions  , 01 - Chain length diagnostic adaptation  .

1. Bolt
   • For aluminum bolts: 4 Nm +90°
   • For steel bolts: 9 Nm
   • Replace after removing
2. Chain Tensioner
   • Is under tension
   • Secure with the Tensioner Locking Tool: T40267  before removing
3. Timing Chain Tensioning Rail
4. Guide Pin
   • 20 Nm
5. Bolt
   • Tightening Specifications and Sequence. Refer to Fig 4.
   • Replace the aluminum bolt after removal
6. Adapter Sleeve
   • Depending on the version, not present on every bearing bracket
7. Control Valves
   • 35 Nm
   • Left-hand thread
   • Different versions depending on the version.
   • Check using the Vehicle Diagnostic Tester Fig 2.
8. Bearing Bracket
   • Assembly instructions. Refer to Fig 3.
   • Removing and Installing. Refer to BEARING BRACKET, REMOVING AND INSTALLING, ENGINE WITH TWO CAMSHAFT ADJUSTERS .
9. Camshaft Timing Chain Guide Rail
10. Camshaft Housing
11. Camshaft Timing Chain
    • Before removing, mark the running direction with paint
    • Removing and Installing. Refer to CAMSHAFT TIMING CHAIN, REMOVING AND INSTALLING, ENGINE WITH TWO CAMSHAFT ADJUSTERS .
12. Camshaft Timing Chain Guide Rail
13. Guide Pin
    • 20 Nm
14. Three Stage Chain Sprocket
    • Crankshaft
    • Installation position. Refer to Fig 5.

Checking the Control Valve 

• The piston -1- must be pushed in approximately 3 mm against the spring force. It must not become stuck while doing so.

Bearing Bracket - Assembly Instructions 

If a new bearing bracket -3- with adapter sleeve -4- should be installed, it must be checked before installing the bearing bracket in the hole -arrow- in the cylinder head -1-.

If the hole -arrow- is not designed for using the adapter sleeve -4- the adapter sleeve must be removed from the bearing bracket. A shorter bolt -2- must also be used for this hole. Refer to the Parts Information for the bolt.

Bearing Bracket - Tightening Specifications and Sequence 

-- Tighten the bolts in the steps in the sequence shown:

For Steel Bolts 

Step	Bolts	Tightening Specifications
1.	-1 to 6-	Install all the way by hand
2.	-1 to 6-	9 Nm

For Aluminum Bolts 

• Replace bolts that were tightened with an additional turn after removing them.

Step	Bolts	Tightening Specification/Additional Turn
1.	-1 to 6-	Install all the way by hand
2.	-1 to 6-	4 Nm
3.	-1 to 6-	180° additional turn

Three Stage Chain Sprocket - Installed Position 

• Both surfaces -arrows- must align.