Installing Camshafts (engine removed)

Installing camshafts, engine removed




Tools

Requirements
Oil pump with coolant guide housing, intermediate shaft flange, belt pulley and guide rails fitted on the crankcase.





1. Move camshaft to basic position. Turn crankshaft clockwise until the bore 1 OT (top dead center) in the belt pulley is aligned with the fixing bore on the crankcase. Position or fix with fixing pin (short) of special tool 9595.





2. Fit auxiliary chain tensioner of special tool 9599 on the crankcase half of cylinder bank 4 - 6. Fit auxiliary chain tensioner without sealing ring and fasten on the crankcase only hand-tight. Adjust pretension with the hexagon-head bolt. The necessary pretension force has been achieve when the measuring pin is flush with the face surface of the pressure screw.
3. Turn engine by 90° on assembly support until cylinder bank 1 - 3 faces upwards.





4. Fit cylinder head gasket. The gasket is identified by Cyl. 1 - 3 and OBEN/TOP, plus the corresponding part number. Ensure correct seating of dowel sleeves in crankcase.




Cylinder bank 1 - 3

5. Fit cylinder head. The cylinder heads differ in the area of the chain tensioners and are therefore marked on the front with 1 - 3 or 4 - 6 to prevent mix-ups.

5.1 Tightening torques and tightening sequence: refer to Removing and installing valve springs.
5.2 Fit shield. Tightening torque of the hexagon-head bolt M6 x 16: 10 Nm (7.5 ft. lbs.)





Note: The shield is fitted only on cylinder head 1 - 3.





6. Fit guide for valve tappets. Tighten pan-head screws (M6 x 35) from the inside to the outside. Tightening torque: 10 Nm (7.5 ft. lbs.)
7. Lightly oil the valve tappet and fit it in the guide.





8. Lay the completely preassembled unit, camshafts with chain and tensioning element into the cylinder head. The groove on the inlet camshaft or the lug on the camshaft position sensor cover faces upward.





9. Align camshafts accordingly and fasten with holding-down device, special tool 9611, and holding-down device, special tool 9624.





9.1 Fasten holding-down device 9611 with auxiliary screws M6 x 45.





9.2 Fit holding-down device 9624 on the cylinder head using a M8 x 30 hexagon-head bolt.





10. Check dowel sleeves (4 ea.) of the bearing saddles to ensure that they are properly seated in the cylinder head. Grease bearing surface, fit bearing saddles in correct position and tighten evenly. Tightening torque: 10 Nm (7.5 ft. lbs.) It is essential to compare the pairing numbers of cylinder head, cylinder head cover and bearing saddles.
11. Fit tensioning element (VarioCam). Tighten 3 M6 x 95 pan-head screws. Tightening torque: 10 Nm (7.5 ft. lbs.)
12. Unscrew tensioning screw, special tool 9632, from the tensioning element.





13. Fit sprocket wheel with chain on the flange of the exhaust camshaft. Fasten guide rail. Tightening torque: 10 Nm (7.5 ft. lbs.)





14. Position drive plate on the sprocket wheel. Fit hexagon-head bolts M6 x 15 (10.9). Tighten hexagon-head screws by hand so that the sprocket wheel can still be rotated.
15. Fit auxiliary chain tensioner of special tool 9599 on cylinder head 1 - 1 Fit auxiliary chain tensioner without sealing ring and fasten on the cylinder head only hand-tight. Adjust pretension force with the hexagon-head bolt. The necessary pretension force has been achieved when the measuring pin is flush with the face surface of the pressure screw.





15.1 Slightly tighten hexagon-head bolt on the sprocket wheel to 10 Nm (7.5 ft. lbs.).
16. Remove holding-down device, special tool 9611.





17. Holding-down device 9624 remains on the cylinder head until the cylinder head cover is fastened.





18. Prepare cylinder head cover for installation: Clean sealing surface of the cylinder head and cylinder head cover very carefully. Apply a silicone bead to the cylinder head cover.
Carefully place the cylinder head cover in the correct position so that the sealing bead is not damaged. Screw two studs or centering pins into the corners of the cylinder head as centering aids.
Immediately remove silicone material emerging in the area of the camshaft closure cap.





19. Remove holding-down device 9624 from the cylinder head.

Note: Fine adjustment of the camshafts is performed after installation of the camshafts in cylinder bank 4 - 6.

Installing camshafts of cylinder bank 4 - 6
1. Turn engine to installation position on assembly support. Remove fixing pin. Advance crankshaft 360° clockwise until the bore 1 OT (top dead center) in the belt pulley is aligned with the fixing bore on the crankcase. Position or fix with fixing pin (short) of special tool 9595.





1.1 Turn engine 90° counterclockwise on the assembly support until cylinder bank 4 - 6 faces up.





2. Fit cylinder head. Observe identification on the cylinder head.





2.1. Fit cylinder head gasket. The gasket is identified by Cyl. 4 - 6 with OBEN/TOP, plus the corresponding part number. Ensure correct seating of dowel sleeves in crankcase. Fit gasket.
3. Fit guide housing for valve tappets.





4. Lay the completely preassembled unit, camshafts with chain and tensioning element into the cylinder head. The groove on the inlet camshaft or lug of the camshaft position sensor cover must face downward.





5. Align camshafts accordingly and fasten with holding-down device, special tool 9611, and holding-down device, special tool 9624.





5.1 Fasten holding-down device 9611 with auxiliary screws M6 x 45.





5.2 Fit holding-down device 9624 on the cylinder head using a M8 x 30 hexagon-head bolt.





6. Check dowel sleeves (4 ea.) of the bearing saddles to ensure that they are properly seated in the cylinder head. Grease bearing surface, fit bearing saddles in correct position and tighten evenly.
Tightening torque: 10 Nm (7.5 ft. lbs.) It is essential to compare the pairing numbers of cylinder head, cylinder head cover and bearing saddles.
7. Fit tensioning element (VarioCam). Tighten 3 M6 x 95 pan-head screws. Tightening torque: 10 Nm (7.5 ft. lbs.)
8. Unscrew tensioning screw, special tool 9632, from the tensioning element.





9. Fit sprocket wheel with chain on the flange of the exhaust camshaft. Fasten guide rail.
Tightening torque: 10 Nm (7.5 ft. lbs.)
10. Position drive plate on the sprocket wheel. Fit hexagon-head bolt M6 x 15 (10.9). Tighten hexagon-head bolts by hand only.
11. Fit auxiliary chain tensioner of special tool 9599 on cylinder head 4 - 6. Fit auxiliary chain tensioner without sealing ring and fasten on the crankcase only hand-tight. Adjust pretension force with the hexagon-head bolt.





11.1 Slightly tighten hexagon-head bolts on the sprocket wheel to 10 Nm (7.5 ft. lbs.).
12. Remove holding-down device 9611.





13. Holding-down device 9624 remains in the cylinder head until the cylinder head cover is fastened.





14. Prepare cylinder head cover for installation: Clean sealing surface of the cylinder head and cylinder head cover very carefully. Apply a silicone bead to the cylinder head cover.
Carefully place the cylinder head cover in the correct position so that the sealing bead is not damaged. Screw two studs or centering pins into the corners of the cylinder head as centering aids.
Immediately remove silicone material emerging in the area of the camshaft closure cap.
15. Remove holding-down device 9624 from the cylinder head.