Position Camshaft For Removal Of Cylinder Head Cover - AR05.20-P-6991-01MFG

Engine 139 in model 118, 177, 247 

Fig 1: Identifying Adjustment Tool (139 589 00 21 00)

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Fig 2: Identifying Counterholder (654 589 00 40 00)

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Disconnect on-board electrical system battery (G1) before removing or installing camshafts.

This causes the CAMTRONIC (Y49/22 or Y49/23) actuators to be re-initiated during commissioning.

When the engine is switched off, the cam positions of the CAMTRONIC actuators (Y49/22 or Y49/23) move in the direction of the performance cam (5). Do not remove or install the cylinder head cover and camshafts in this position.

When the engine is switched off, the exhaust camshaft is positioned on the performance cams (5). Do not remove or install the cylinder head cover and camshaft in this position.

Otherwise the performance cam (5) pushes the camshaft upward when the cylinder head cover is removed and the guide bearing of the camshaft may be damaged.

Only remove the cylinder head cover once the CAMTRONIC actuators (Y49/22 or Y49/23) are in the position of the turbo activation cam (6).

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1. Rotate engine at center bolt of crankshaft and set cylinder 1 (1) of engine to ignition TDC.
2. Install adjusting tools.

   Pin of adjusting tool at cylinder 1 and 2 (1, 2) is up and half down at cylinder 3 and 4 (3, 4).

   Cylinder 1 (1) at ignition TDC 

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3. Rotate engine at center bolt of crankshaft by 4x 360° in direction of engine rotation .

   Pin of adjusting tool at cylinder 1 and 2 (1, 2) is half down and fully down at cylinder 3 and 4 (3, 4).

   1st turn = 360° (cylinder 1 (1) overlap) 

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   Pin of adjusting tool at cylinder 1 and 2 (1, 2) is fully down and fully down at cylinder 3 and 4 (3, 4).

   2nd turn = 720° (cylinder 1 (1) ignition TDC) 

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   Pin of adjusting tool at cylinder 1 and 2 (1, 2) is fully down and fully down at cylinder 3 and 4 (3, 4).

   3rd turn = 1080° (cylinder 1 (1) overlap) 

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   Pin of adjusting tool at cylinder 1 and 2 (1, 2) is fully down and up at cylinder 3 and 4 (3, 4).

   Cylinder 1 (1) is at ignition TDC.

   4th turn = 1440° (cylinder 1 (1) ignition TDC) 

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4. Remove adjustment tools.

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   Both CAMTRONIC actuators (Y49/22 or Y49/23) are now on turbo activation cam (6).

   Cylinder head cover can now be removed.