Checking Timing Of Camshafts

NOTIFICATION 

Timing not set correctly 

• Risk of engine damage 
• Rough running engine 
• Loss of engine power 
  1. → Do not use force when firing the staking tool.
  2. → Make sure that the gap is equal on both sides.
  3. → When inserting the staking tools, do not use force to turn the camshafts against any resistance.
  4. → The engine must be exactly at top dead centre.
  5. → The opposite cylinder must be at ignition TDC.

Information 

An offset from one tooth indicates a deviation from the setpoint value of approx. 6 mm.

If an offset is detected, the timing chain must be re-fitted.

1. Remove bearing saddle -1-  .
   1. 1.1  Unscrew screws -2-  .
   2. 1.2  Carefully loosen and remove the bearing saddle -1-  .

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   Bearing saddle

   Information 

   If the crankshaft was turned beyond the TDC position, the engine must be turned another two turns in direction of rotation of the engine  until it is back at TDC.

   The engine must not be turned against the direction of rotation of the engine. 

2. Turn the crankshaft using a suitable tool until the markings -Arrows-  on the camshaft timing gears are facing upwards.

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   Markings on camshaft timing gears

   Information 

   If the crankshaft was turned beyond the TDC position, the engine must be turned another two turns in direction of rotation of the engine  until it is back at TDC.

   The engine must not be turned against the direction of rotation of the engine. 

   Information 

   Once maximum pointer deflection is reached, the piston is at top dead centre (TDC). 

3. Move cylinder 1 to TDC position.
   1. 3.1  Prepare VAS 6079 - Dial gauge-2-  .
      1. 3.1.1 T10170A - Dial gauge adapter-1-  must be screwed fully into the spark plug bore of cylinder 1.
      2. 3.1.2  Insert VAS 6079 - dial gauge-2-  into T10170A - dial gauge adapter-1-  and clamp securely with a clamping nut.
   2. 3.2  Turn the engine slowly in direction of rotation of the engine until maximum deflection of the pointer on the VAS 6079 -dial gauge-2-  is reached.

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   Dial gauge on cylinder 1

4. Check TDC markings.
   1. 4.1  Check that the markings on the camshaft timing gears -2-  are still pointing to the markings on the cylinder head cover -1-  .

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   TDC markings on crankshaft and camshafts

5. Check timing of camshafts.
   1. 5.1  Measure dimension -1-  between the edge -arrow A-  and the marking on the outlet camshaft -arrows B-  using a calliper gauge.

      Make sure that measurement takes place in parallel with the timing chain to prevent incorrect measurements.

   2. 5.2  Compare the measured value with the setpoint value.

      control value (minimum) 74 mm 

      control value (maximum) 77 mm 

      If the measured value is within the setpoint value range: Measure dimension -1-  . Otherwise: Set timing for camshafts.

   3. 5.3  Measure dimension -2-  between the marking on the outlet camshaft -arrow B-  and the marking on the intake camshaft -arrow C-  using a calliper gauge.

      Make sure that measurement takes place in parallel with the timing chain to prevent incorrect measurements.

   4. 5.4  Compare the measured value with the setpoint value.

      control value (minimum) 124 mm 

      control value (maximum) 127 mm 

      If the measured value is within the setpoint value range: The timing is OK. Remove the dial gauge and special tools.

      If the measured value is not  within the setpoint value range: Set timing for camshafts.

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   Camshaft timing