Removing Chain Housing Cover

NOTIFICATION 

Chain housing cover removed incorrectly 

• Risk of damage to seal between oil pan and crankcase 
• Risk of engine leaks 
  1. → Always reseal the oil pan when removing the chain housing cover.

1. On turbo engines, remove positive crankcase ventilation completely in front of the chain housing cover One-way couplings for ventilation on turbo engines.  Be careful with connections that cannot be loosened.
   Fig 1: One-Way Couplings For Ventilation On Turbo Engines Components Location

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   One-way couplings for ventilation on turbo engines

   1	Turbocharger/manifold module
   2	Check valve on vent line for oil mist separator and Intake-air distributor
   3	Full-throttle ventilation one-way coupling => Cannot be refitted. Make sure the markings are positioned correctly with respect to each other during initial fitting.
   4	Full-throttle ventilation one-way coupling to intake manifold => Cannot be refitted. Make sure the markings are positioned correctly with respect to each other during initial fitting.

2. Remove belt tensioner and deflection rollers on the chain housing cover. To do this, lever off the cover and loosen the screws. Beit drive
   Fig 2: Belt Drive Components Location

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   Belt drive

   1	Deflection roller
   2	Hydraulic belt tensioner; tensioner at the lever, tensioning roller at the tensioning lever
   3	M8 screw; complete lever on chain housing cover and cylinder head; belt tensioner and chain housing cover at the console
   4	Deflection roller
   5	Dual poly V-belt

3. Unclip vacuum lines from the cable duct if fitted Unclipping vacuum lines at the cable duct. 

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   Unclipping vacuum lines at the cable duct

4. Unscrew fastening screw -1-  at the cable duct -arrows-  .

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   Loosening cable duct

5. Remove chain tensioner.

   > 153619 REMOVING AND INSTALLING CHAIN TENSIONER 

6. Remove chain housing cover. To do this, loosen all screws in reverse order. Tightening sequence for chain housing cover 
   Fig 3: Chain Housing Cover Screws Tightening Sequence

   Courtesy of PORSCHE CARS NORTH AMERICA, INC.

   Tightening sequence for chain housing cover

   A	Screw, M6
   B	M6 screw; inner chain housing cover to upper part of crankcase and cylinder head; chain housing cover to
   	cylinder head
   C	M8 screw; chain housing cover (chain tensioner position) to upper part of crankcase and cylinder head
   D	The chain housing cover must be level with the lower part of the crankcase (use a steel rule or dial gauge)

7. Carefully remove chain housing cover. Lever off gently if necessary (bonded with sealant).