Porshe 911 (997). Manual - part 61

14. Insert guide rail screw with a new O-ring and tighten (hexagon socket M6, a/f 5) Grease O-ring

with Optimol MP3. → Tightening torque: 7.5 ftlb.

Chain tensioner, cylinders 4 - 6

15. Fit chain tensioner, side 4 - 6 (hexagon socket a/f 14). Fit chain tensioner with new aluminium

sealing ring and tighten. → Tightening torque: 59 ftlb.

Pulley fixed at TDC marking

Note

Position crankshaft above the pulley or vibration balancer before final adjustment of the timing to the
TDC marking.

• 

16. Turn the crankshaft by means of the pulley or vibration balancer clockwise (running direction of engine

to TDC mark : marking U6 on pulley or vibration balancer coincides with fixing bore in crankcase.
Fix with locating pin 9595/1.

Exhaust camshaft sprocket tightened

17. Insert four Torx screws M6 to sprocket of exhaust camshaft and tighten evenly in diagonally

opposite sequence. → Tightening torque: 10.5 ftlb.

Diagnostic system: reading out fault memory and activating systems

Installing camshafts, adjusting timing - engine removed

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Contact block at the fitting bore of the cylinder head

18. Tighten the central screw of the camshaft adjusting device. Fit special tool retaining tool 9685 on

hexagon of intermediate piece of the central screw. Screw in the central screw gently by hand so that the
loose contact block just touches the fitting bore of the oil suction pump. Fix the hexagon-head bolt to the
contact block.

Tighten central screw of camshaft adjusting device.

Note

Before final tightening (torque angle) of the central screw, the special tool adjusting gauge 9686
must be removed.

• 

19. Tighten the central screw in two stages. Initial tightening to the specified toque. → Initial

tightening: 37 ftlb.

20. Remove special tool adjustment gauge 9686. Undo the M8 screw and remove gauge.

21. Apply final tightening to central screw with torque angle wrench. → Final tightening torque angle:

110 °

Assembly of cylinder bank 1 -3

22. Turn the engine on the assembly support until cylinder bank 1 - 3 stands vertically upwards.

Diagnostic system: reading out fault memory and activating systems

Installing camshafts, adjusting timing - engine removed

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Pulley fixed at 60° before TDC

23. Turn the crankshaft by means of the pulley or vibration balancer clockwise (running direction of

engine

 further still until the marking U6 on pulley or vibration balancer coincides with fixing

bore in crankcase

 (60° before TDC). Fix with locating pin 9595/1.

24. Oil the bearing surfaces of the camshafts with new engine oil.

Inlet camshaft 1-3 in overlap

25. Insert inlet camshaft 1 - 3. Pull the control chain out of the chain housing of the cylinder head with a

welding wire and position on the toothed ring of the camshaft adjuster. Then insert the camshaft at
overlapping TDC of cylinder 1 (the cams of cylinder 1 point diagonally downwards towards the outside
of the cylinder head -arrow- ).

Position of bearing sleeve for inlet camshaft

Note

Make sure that the bearing sleeve on the inlet camshaft is positioned correctly.

• 

26. The bearing sleeve of the inlet camshaft must be positioned so that the centrally bored blind hole points

vertically upwards -arrow- (the rib of the cylinder head should also be at the centre in relation to the
bearing sleeve). In this position, the dowel pin in the bearing bore of the cylinder head will fit precisely

Diagnostic system: reading out fault memory and activating systems

Installing camshafts, adjusting timing - engine removed

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into the opposite off-centre blind hole bore. Any other bores are through-holes for guiding the oil.

Exhaust camshaft 1-3 in overlap

27. Insert exhaust camshaft 1 - 3. Lay the control chain on the flange for the chain sprocket, then insert the

camshaft at overlapping TDC of cylinder 1 (the cams of cylinder 1 point diagonally downwards towards
the outside of the cylinder head).

Exhaust sprocket 1 - 3 at 60° before TDC

28. Insert exhaust camshaft sprocket in the timing chain and position on camshaft flange. The four

threaded bores in the camshaft flange must be fully visible on the left at the slotted curves of the
sprocket -arrows-

 so that the Torx screws M6 x 12 can still be positioned to fasten the sprocket.

Exhaust sprocket 1 - 3, all screws fitted

Diagnostic system: reading out fault memory and activating systems

Installing camshafts, adjusting timing - engine removed

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