Prepare tools "11.9.470" and "11.9.473". Remove the left eccentric shaft adjustment drive motor and the ignition coils of cylinders 5–8. Remove the left cylinder head cover, unscrew the spark plugs of cylinders 5–8 and the left VANOS actuators for intake and exhaust.
Caution! Turn the intake camshaft so that when removing the support bridge, the intermediate levers do not slip and damage the camshaft.
Turn the intake camshaft counterclockwise so that the inscription (1, Fig. 5.132) was facing upwards in the direction of the axis of the 8th cylinder, and the cam (arrow) stood horizontally.
The bearing caps of the intake camshaft on cylinder bank 5–8 are marked "RE1–RE5", read from the intake side. Loosen the mounting nuts (arrows, Fig. 5.133) and remove the bearing cover "RE1".
Loosen and unscrew the eight nuts (arrows, Fig. 5.134) fastening the support crossbar (1), starting from the outer nuts and moving towards the center.
Attention!
- When removing the support crossbar, do not turn it over.
- Push rods are divided into tolerance classes.
- On the intake side, only tappet levers of one tolerance class can be installed per cylinder. Tolerance classes are designated by numbers from 1 to 4.
- Old class 1 and 2 correspond to the new "2a", class 3 and 4 - "2b".
Clamp the device "11.9.470" in a vice. Carefully remove the support bridge from the cylinder head by moving it upwards. Do not turn the support bridge over and place the support bridge together with the intake camshaft and the eccentric shaft, as shown in Figure 5.135, on the device "11.9.470". Secure the support bridge (1) with a nut (device "11.9.473").
Caution! The lower part of the support bridge is machined together with the cylinder head and therefore cannot be repositioned. It remains on the cylinder head.
Removal of intermediate levers should begin with the 8th cylinder, for cylinders 5-7 the actions are similar. Removal of intermediate levers should begin with the 8th cylinder, for cylinders 5-7 the actions are similar.
Remove the levers (1, see Fig. 5.98) roller tappets on the intake side and stack them in order.
Inspect the intake camshaft and replace the rings if necessary (1, see Fig. 5.103) rectangular cross-section, as they break easily. The rings (1) of rectangular cross-section snap into place at the joint. To remove the ring, it is necessary to press it in from one side (left arrow) into the groove, and on the other side pull it up (right arrow) and release the lock. Carefully spread the ring (1) and remove it by moving it forward.
The installation of the intake camshaft pushrod lever on cylinder bank 5–8 must be carried out in the following order, starting with the 8th cylinder.
Clean all bearing beds and intake camshaft cams with engine oil. Insert rectangular rings. Start installation with the far ring. Be extremely careful, rings break easily. Carefully spread the ends of the ring and install it in the groove. Press the end of the rectangular ring into the groove and hook it with a retainer on the other side. Make sure that the ends of the rings are facing up and their locks are snapped into place (see fig. 5.106).
Caution! The push rods move easily when installing the support bridge. Do not turn the support bridge over.
Install roller tappet levers on the intake side (see fig. 5.98). Make sure it is fixed to the hydraulic valve clearance compensation system elements and their valves. Align the valve lifter levers and remove the "11.9.473" device (see fig. 5.135).
Remove the device "11.9.470" from the support crossbar, install it (1, see Fig. 5.134) movement from top to bottom and carefully bring into contact with the cylinder head. Install the nuts (M7) and tighten them by hand until they touch the support crossbar.
Attention!
Make sure that the intermediate levers and pushrod levers are in place and have not slipped.
Bearing caps of camshafts of cylinders 1–4 and 5–8 cannot be interchanged.
Tighten the nuts (M7) from the middle to the edges, with a torque of 14 N·m (1.4 kgf·m).
Install the bearing cover "RE1" so that the marking (see fig. 5.133) read from the intake side. Install the nuts (M7) and tighten them to a torque of 14 N·m (1.4 kgf·m).
Turn the intake camshaft in the direction of rotation so that the cam of the 5th cylinder takes the inclined upper position (arrow, Fig. 5.136), as shown in the figure.
The marking (1) on the hexagon of the intake camshaft is located at the top.
Install the left VANOS intake and exhaust actuators, screw in the spark plugs for cylinders 5–8, install the left cylinder head cover and the ignition coils for cylinders 5–8.
Install the left eccentric shaft drive motor and assemble the motor.
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