Installing Camshafts, Setting Timing - Cylinder Bank 1 -3
- Risk of damage to units or components
→ Protect components from dirt and contamination.
→ Clean or replace dirty components.
- Too much wear on sprockets and timing chains
- Engine damage
→ Perform a visual inspection to check the position of the timing chains on the tensioning and guide rails.
Information
- Before final tightening (torque angle) of the central screws, the > 9772/1 - staking tool must be removed.
- Replace the hexagon sleeves for the central screws.
Installation is always performed when setting the timing as for bank 4-6!
- Re-secure the crankshaft.
> 9595/1 - Locating pin must then be removed.
Turn the crankshaft at the vibration damper 360 degrees clockwise (running direction of engine) to TDC position of cylinder 1/4.
The position is marked by A and OT 1.
Use a long > 9595/1 - locating pin-1 - to fix the vibration damper in place.
TDC position of vibration damper
- Turn the engine at the assembly support so that the cylinder bank to be worked on is at the top.
- Oil the bearing locations and camshafts with new engine oil. When rebuilding the engine, apply a light coating of Optimol Optipit grease (Part No. 000.043.204.17).
Check that all hydraulic tappets are installed correctly.
- Insert camshafts -1 and 2-
.
Insert camshafts -1 and 2- into the cylinder head in such a way that the cams -Arrows- are pointing outwards at an angle, towards the cylinder head wall and the camshafts -1 and 2- are not tensioned.
Check whether the data matrix code markings on the dihedron are facing you.
Cam position of cylinder 1 at overlapping TDC
1 Intake camshaft 2 Outlet camshaft - Secure camshafts -1 and 2-
.
> 9772/1 - Staking tools-3- must be fitted on the dihedron of the camshafts.
Position tools on the Centre bearing cover supports on the camshafts and tighten cheese head bolts -1- slightly, making sure that the adjusting screws -5- are sticking out far enough and are not touching the camshafts.
Staking tool 9772/1 on cylinder bank 1-3
1 Intake camshaft 2 Outlet camshaft 3 Staking tools 4 Cheese head bolts 5 Adjusting screws - Install bearing saddle and bearing covers.
Do not install the Centre bearing covers until you have set the timing.
Fit bearing saddle and bearing covers. Observe markings while doing this.
Fit bearing saddle screws -13 to 16- .
Fit and tighten screws for bearing covers -3 to 6- and -9 to 12- .
Courtesy of PORSCHE CARS NORTH AMERICA, INC.
Tightening sequence for camshaft bearing cover
Fit and tighten screws in ascending sequence (except -1 and 2- and -7 and 8- ).
- Tool recommendation: >
9768 - Electronic torque wrench, 2 - 100 Nm (1.5 - 74ftlb.)
Screws, M6 x 38:
> Initial tightening 5 Nm (3.5 ftlb.)
> Torque angle 50 Grad
Screws, M6 x 70 (bearing saddle):
> Initial tightening 5 Nm (3.5 ftlb.)
> Torque angle 90 Grad
Courtesy of PORSCHE CARS NORTH AMERICA, INC.
Tightening sequence for camshaft bearing cover
- Check that the new friction plates -2-
are inserted into the camshaft controllers -3-
.
Friction plate in camshaft controller
- Install camshaft controllers -1 and 2-
.
Fit camshaft controllers -1 and 2- with new friction plates on camshafts.
Install the timing chain.
Tighten central screws -3- with new drivers slightly by hand.
Installation overview of central screws for camshaft controllers
1 Camshaft controller, intake 2 Camshaft controller, outlet 3 Central screws (central valves) - Use a torch to check that the timing chains -1-
are on the tensioning and guide rails between the guide pins -Arrows-
.
Position of timing chain in tensioning and guide rails
- Screw in and tighten chain tensioner with old seal.
Use chain tensioner 9A1.105.157.02 (1st generation 991 engine) for setting the timing.
> Tightening torque 80 Nm (59 ftlb.)
Set the timing for bank 1-3: The timing for cylinder bank 1-3 is set in the same way as for cylinder bank 4-6!
- > 9772/1 - Staking tools must be tightened hand-tight with the cheese head bolts.
- Tighten adjusting screws -1-
of the staking tools slowly on both sides.
Do not exceed the specified tightening specification (tool will become tilted)!
> Tightening torque 2 Nm (1.5 ftlb.)
Adjusting screws on staking tools
- Pre-tighten central screws.
Tools:
- -item 1- : > 9863/3 - Open-ended wrench, a/f 39 for countering
- -item 2- : > 9863 - Socket wrench for camshaft
- -item 3- : > V.A.G 1332 - Torque wrench. 40-200 Nm (30-148 ftlb.)
Pre-tighten central screws and use > 9863/3 - open-ended wrench, a/f 39 to counter at the hexagon driver -Arrow- .
> Initial tightening 30 (22 ftlb) Nm
Central screw for camshaft controller (view of intake side)
- Check axial bearing play at the camshafts (by gently pulling and pressing on the camshaft controllers).
If there is not a clearly perceptible amount of play, the shafts will have to be re-fitted.
- >
9772/1 - Staking tools
must now be removed.
Loosen adjusting screws.
Unscrew cheese head bolts on the bearing cover supports and remove tools.
- Install Centre bearing covers at the camshafts.
Fit Centre bearing covers.
Fit and tighten screws uniformly.
> Initial tightening 5 Nm (3.5 ftlb.)
> Torque angle 50 Grad
- Tighten central screws to their final tightening torque.
Tools:
- -item 1- : > 9863/3 - Open-ended wrench, a/f 39 for countering
- -item 2- : > 9863 - Socket wrench for camshaft
- -item 3- : > 9768 - Electronic torque wrench. 2 -100 Nm (1.5 - 74 ftlb.)
Tighten central screws and set threshold torque on the electronic torque wrench to 30 Nm (22 ftlb.).
> Final tightening torque angle 40 Grad +/- 5 Grad
Tightening camshaft controllers - bank 4-6
- Unscrew replacement chain tensioner and screw in and tighten original chain tensioner with a new seal.
> Tightening torque 80 Nm (59 ftlb.)
- Then check the position of the camshafts on both sides again (always check overlapping position!).