Part 1
Removing and installing camshafts (includes setting timing)
Preliminary work
1. Remove the engine.
2. Remove engine carrier.
Engine carrier and holder for front silencer
3. Remove rear silencer.
4. Remove exhaust manifolds. Unscrew nine M8 x 21 screws on each and remove manifold and seal.
5. Remove holder for rear silencer.
5.1. Unscrew four M8 x 20 Torx screws and remove holder.
6. Remove heat shield for ignition coils.
7. Remove bar ignition modules.
7.1. Pull off cable plugs on bar ignition modules, hall sender and solenoid hydraulic valve (VVS) and unscrew two M6 x 12 cheese head bolts for the ground cables for the bar ignition modules.
7.2. In each case, unscrew one internal Torx (T30) countersunk screw (M6 x 16) and pull the ignition coils out of the spark-plug recess.
8. Remove spark plugs.
9. Remove high-pressure pump.
10. Remove vacuum pump.
11. Remove cover for positive crankcase ventilation.
11.1. Cover on cylinder bank 1-3 -1-: Unscrew three external Torx screws (M6 x 20) -4- and replace O-ring -3- and moulded seal -2-.
Cover on positive crankcase ventilation 1-3
11.2. Cover on cylinder bank 4-6 -1-: Unscrew two external Torx screws (M6 x 20) -3- and replace O-ring -2-.
Cover on positive crankcase ventilation 4-6
12. Remove cylinder head cover.
Removal
Removing camshafts
Notice
Dirt and contamination
^ Risk of damage to units or components
-> Protect components from dirt and contamination.
-> Clean or replace dirty components.
Information
Specifications for wrench sizes (a/f specifications) for screw heads are described as follows:
^ Torx screws: (E..) for external Torx, (T..) for internal Torx.
^ Hexagon-head bolts (internal and external hexagon): Wrench size (a/f)
Overview (view of cylinder bank 4-6):
Component overview for camshafts/cylinder head
1 - Intake camshaft 4-6
2 - Outlet camshaft 4-6
3 - Camshaft mounting saddles
4 - External Torx screw, M6 x 37
5 - Bearing saddle (upper part)
6 - Bearing saddle (lower part)
7 - External Torx screw, M6 x 55
8 - Dowel sleeves for cylinder head
9 - Bucket tappets (exhaust)
10 - Switchable bucket tappets (intake)
11 - Friction plate (diamond washer)
12 - Sprocket 4-6
13 - Central screw M12 x 1.5 x 60
14 - Camshaft actuator
15 - Hexagon
16 - Central screw M12 x 1.5 x 110
17 - Position of matching number on cylinder head
Information
^ The camshafts can only be removed in the overlapping position at the top dead center of pistons 1 or 4.
^ Only at this position can you be sure that the valves are not touching against the pistons and cannot be damaged when the engine turns.
1. Turn the engine at the assembly support so that the cylinder bank to be worked on is at the top.
2. Use special tool turning device 9773 -1- to turn the crankshaft clockwise at the vibration damper as far as the TDC marking on cylinder 1/4.
TDC marking on cylinder 1/4 at vibration damper
2.1. Fix the vibration damper in place above the staking bore using a locating pin 9595/1 -2-.
2.2. Check the position of the data matrix code on both camshafts. These must be facing the observer at overlapping position.
3. Check cam position on cylinders 1 and 4.
3.1. Overlapping position of cylinder 1: The cams must be facing downwards at an angle to the cylinder head wall -arrows-.
Cam position on cylinder 1 at overlap
1 - Outlet camshaft 1-3
2 - Intake camshaft 1-3
3.2. Overlapping position of cylinder 4: The cams are facing each other and are at a slight angle with respect to the spark-plug recess -arrows-.
Cam position on cylinder 4 at overlap
4. Remove central screws on camshaft timing gears.
Central screws on camshaft timing gears
5. Loosen internal Torx central screw (T55, M12 x 1.5 x 60) on the outlet sprocket. To do this, counter with special tool holding wrench 9775 -1-.
Outlet sprocket threaded joint
Camshaft controller threaded joint
6. Loosen internal Torx central screw (T55, M12 x 1.5 x 110) on the camshaft controller. To do this, counter with a long open-ended wrench (a/f 32) -1-.
7. Remove chain tensioner.
7.1. Cylinder bank 1-3: Chain tensioner sifting on underside of the crankcase.
7.2. Cylinder bank 4-6: Chain tensioner sitting on top of cylinder head.
7.3. Replace sealing ring.
8. Loosen four external Torx screws (E10, M6 x 55) on the bearing saddle -2-.
8.1. Then loosen the external Torx screws (M6 x 37) for the mounting saddles from the outside in -1-.
Camshaft mount
9. Lift camshafts out of the cylinder head. Lay the timing chain into the chain housing in the cylinder head.
9.1. Unscrew central screw on the camshaft controller.
9.2. Lift up the camshaft controller -1- with the intake camshaft and pull the shaft -2- to the flywheel side using one hand. Pay particular attention to the friction plate when doing so. Lift up the timing chain and remove the camshaft controller.
Intake camshaft with camshaft controller
9.3. Join the controller to the intake camshaft again for storage. Tighten screw only slightly.
9.4. Remove outlet camshafts complete with the sprocket.
Outlet camshaft with sprocket
10. Replace the friction plates in the sprocket and on the intake camshaft.
Information
^ The camshaft controller must not be cleaned in a parts washer.
^ Only the outside can be cleaned using a clean, lint-free cloth.
11. Clean the components.
11.1. Do not clean the camshaft controller in a parts washer.
Installation
Component markings and distinguishing features
Markings:
Camshafts:
Intake side:
Intake camshafts
1 - 3.8-liter engine, MA 1.01: Intake camshaft (short) on cylinder bank 46, marking: 9A1.014.03 E4-6
2 - 3.8-liter engine, MA 1.01: Intake camshaft on cylinder bank 1-3, marking: 9A1.013.03 E1-3
1 - 3.6-liter engine, MA 1.02: Intake camshaft (short) on cylinder bank 46, marking: 9A1.028.03 E4-6
2 - 3.6-liter engine, MA 1.02: Intake camshaft on cylinder bank 1-3, marking: 9A1.027.03 E1-3
Outlet side:
Outlet camshafts
1 - 3.8-liter engine, MA 1.01: Outlet camshaft (short) on cylinder bank 4-6, marking: 9A1.216.03 A4-6
2 - 3.8-liter engine, MA 1.01: Outlet camshaft on cylinder bank 1-3, marking: 9A1.215.03 A1-3
1 - 3.6-liter engine, MA 1.02: Outlet camshaft (short) on cylinder bank 4-6, marking: 9A1.224.03 A4-6
2 - 3.6-liter engine, MA 1.02: Outlet camshaft on cylinder bank 1-3, marking: 9A1.223.03 A1-3
Distinguishing features of outlet sprockets:
1-3 - Sprocket for outlet camshaft on cylinder 1-3, driver for high pressure pump: Recess 15 mm and 11.6 mm deep.
4-6 - Sprocket for outlet camshaft on cylinder 4-6, driver for vacuum pump, both recesses 11.6 mm deep.
Outlet sprockets
Camshaft mount:
^ Bearing saddle: Matching number for upper and lower part for cylinder head, engraved on front (chain box side).
^ Bearing cover: Matching number for cylinder head and allocation to intake and outlet side of cylinder (e.g. A1 for outlet cylinder 1), engraved.
Installing camshafts, setting timing - cylinder bank 4-6
Notice
Dirt and contamination
^ Risk of damage to units or components
-> Protect components from dirt and contamination.
-> Clean or replace dirty components.
Information
Before final tightening (torque angle) of the central screws, the special tool staking tool 9772 must be removed.
Information
Specifications for wrench sizes (a/f specifications) for screw heads are described as follows:
^ Torx screws: (E..) for external Torx, (T..) for internal Torx.
^ Hexagon-head bolts (internal and external hexagon): Wrench size (a/f)
1. Turn the crankshaft clockwise (running direction of engine) to 60 degrees before TDC at the vibration damper.
1.1. This position is marked U 3/6 on the surface.
Position U 3/6 (60 degrees before TDC)
1.2. Fix in place using a long locating pin 9595/1 -1-.
2. Turn the engine at the assembly support so that the cylinder bank to be fitted is at the top.
3. Fit lower part of bearing saddle -1-.
Lower part of bearing saddle 4-6
3.1. Check position of oil bores and position and fit the component on the dowel sleeves.
4. Oil the bearing surfaces of the camshafts with new engine oil. When rebuilding the engine, apply a light coating of Optimol Optipit grease (Part No. 000.043.204.17) on the bearings.
4.1. Check that all hydraulic tappets are installed correctly.
5. Fit the outlet camshaft and sprocket.
Fitting outlet camshaft and sprocket (view of cylinder bank 1-3)
5.1. Check that the friction plate -1- is fitted in the sprocket.
Friction plate in sprocket
5.2. Screw in the central screw but make sure that the sprocket can still turn.
5.3. Lift the timing chain and position the camshaft and sprocket at the overlapping position of cylinder 4. The cams must be facing downwards at an angle with respect to the spark-plug recess and the camshaft must lie loosely in the bearing positions.
6. Fit the intake camshaft.
6.1. Check that the friction plate -2- is fitted on the shaft -1- (-arrow-).
Position of friction plate on intake camshaft
6.2. Lift the timing chain and engage and secure the camshaft controller -1-. Guide the intake camshaft -2- into the controller and set it to the overlapping position of cylinder 4. The cams must be facing downwards at an angle with respect to the sparkplug recess and the camshaft must lie loosely in the bearing positions.
Fitting intake camshaft (view of cylinder bank 1-3)
6.3. Screw in the internal Torx central screw (T55, M12 x 1.5 x 110) by hand until the controller can still turn.
7. Check cam positions for cylinder 4. The cams must be facing downwards at an angle with respect to the spark-plug recess.
Fitting camshafts for cylinder 4 at overlapping position
1 - Outlet camshaft
2 - Intake camshaft
7.1. Another feature is a data matrix code marking on the reconditioned surface next to the dihedron -inset-. These markings must be facing the observer at overlapping position.
Marking on camshafts 4-6 at overlap
Caution
Timing chains positioned incorrectly
^ 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.
8. Use a torch to check that the timing chains are on the tensioning and guide rails between the guide pins -arrow-.
Guide pins on tensioning and guide rails
9. Oil the bearing surfaces of the camshafts with new engine oil. When rebuilding the engine, apply a light coating of Optimol Optipit grease (Part No. 000.043.204.17) on the bearings.
10. Fit bearing saddle and bearing covers.
10.1. Fit bearing saddle and bearing covers and observe markings.
10.2. Fit four external Torx screws (E10, M6 x 55) on the bearing saddle.
10.3. Fit two external Torx screws (E10, M6 x 37) for each of the bearing covers.
10.4. Fit and tighten screws according to the specified tightening sequence -1 to 16-.
-> Initial tightening: 5 Nm (3.5 ftlb.)
-> Torque angle: 50 degrees
Tightening sequence for mounting camshafts 4-6
11. Check axial bearing clearance by pulling and pressing on the camshaft controller and sprocket.
11.1. There must be perceptible clearance because otherwise the shafts will have to be fitted again.
12. Screw in and tighten chain tensioner with anew seal.
-> Tightening torque: 80 Nm (59 ftlb.)
Set the timing, cylinder bank 4-6:
13. Check cam position for cylinder 4 -arrows-.
Cam position for cylinder 4 at overlap
Data matrix code is facing the observer.
Marking on camshafts 4-6 at overlap
14. The adjusting device is positioned on the reconditioned dihedron of the camshafts -arrows-.
Position of dihedron of camshafts 4-6
14.1. Check the position of the intake and outlet side -arrows-.
A - A = Outlet
E - E = Intake
1 - Staking tool
2 - Staking guide
Fitting position of staking tool for cylinder bank 4-6
15. Fit special tool staking tool 9772 -1- on the cylinder head and camshafts.
15.1. Secure on the cylinder head with four M6 x 25 screws -2-. Tighten screw slightly with your hand.
Staking tool screws for cylinder bank 4-6