Installing Valve Tappets - Cylinder Bank 1 - 3
WM 155924 Installing valve tappets - Cylinder bank 1 - 31. Check guide for damage.
2. Fit guide. Tighten pan-head screws (M6 x 35) from the inside to the outside. Tightening torque 10 Nm (7.5 ftlb.)
3. Lightly oil the valve tappet and fit it in the guide.
4. Lay the complete unit, camshafts with chain and tensioning element in the cylinder head. The groove or tab of the camshaft position sensor cover must face upward If the allocation should be uncertain, e.g. chain jumped over, reallocation is necessary.
5. Special tool 9611; fit holding-down device for camshafts. Fit auxiliary screws M6 x 45 with washers and tighten to 10 Nm (7.5 ftlb.).
6. Check dowel sleeves (4 ea.) of the bearing saddles to ensure that they are properly seated in the cylinder head. Oil bearing surface. Fit bearing saddles in the correct position and tighten evenly. Tightening torque 10 Nm (7.5 ftlb.)
E - Bearing saddle for inlet camshaft
A - Bearing saddle for exhaust camshaft
7. Fit tensioning element (VarioCam). Tighten 3 M6 x 95 pan-head screws. Tightening torque 10 Nm (7.5 ftlb.)
8. Unscrew tensioning screw (special tool 9632) from the tensioning element.
9. Remove tie wrap and fit sprocket wheel with chain on the flange of the exhaust camshaft.
10. Position drive plate or driver star on the sprocket wheel. Fit hexagon-head bolts M6 x 15 (10.9). Tighten hexagon-head bolts by hand only.
11. Unscrew chain tensioner (fitted on the crankcase half of cylinder bank 4 - 6) and fasten auxiliary chain tensioner (special tool 9599).
12. Fit auxiliary chain tensioner without sealing ring and fasten on the crankcase only hand-tight. The mechanical auxiliary chain tensioners must be install with the correct pre-tension when the valve timing is adjusted or checked. The necessary pre-tension force has been achieved when the measuring pin is flush with the face surface of the pressure screw. Turn the screw if necessary.
13. Fit auxiliary chain tensioner on cylinder head 1 - 3 and adjust pretension force (refer to step 12).
14. Fit cylinder head cover. Remove holding-down device 9611. 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. For the subsequent adjustment work on the camshaft, the pulley must be fixed at bore 1 OT (TDC) with the fixing pin special tool 9595).
16. Fasten blocking device (special tool 9612) on the cylinder head.
Special tool fitting sequence:
A - Fastening screw with star knob on cylinder head lug. Pull back B and C when tightening.
B - centering piece in groove of the exhaust camshaft.
Pull sword bolt (C) back when tightening.
C - Sword bolt
17. Allocate camshafts; to do this, turn the pre-tensioned center piece accordingly until the sword bolt can be fixed in the bearing bore.
18. Fasten sprocket wheel. Tightening torque 14 Nm (10.5 ftlb.)
19. Remove blocking device.
Information
^ The auxiliary chain tensioners must remain fitted on cylinder bank 4 - 6 for the subsequent assembly work.
20. Fit oil extraction pump
Information
^ The oil extraction pumps on the cylinder heads are identical parts. Therefore, the installation position and direction of rotation must be correct.
Installation position of oil extraction pump at cylinder head 1 - 3 (flywheel side).
The arrow for the direction of rotation or the marking "1 - 3" must face the crankcase.
Fit oil extraction pump. Use new sealing ring and new micro-encapsulated hexagon socket head screws.
Tightening torque 10 Nm (7.5 ftlb.)
21. Fit camshaft closure cap dry.
22. Fit closure capon tensioning element (VarioCam). Tightening torque 10 Nm (7.5 ftlb.)