Installation
InstallationInstallation of camshafts is described separately from removal.
Assembly sequence for removal and installation is different.
Note: Camshafts, bearings and bearing caps, thrust washers, all splines on toothed shafts and spline hubs must be oiled before installation.
Caution: The bucket tappets expand when not subjected to load by the camshaft and therefore require some time before they can be pushed back down. During a rapid assembly sequence, the "closed" valves may still be open and be in contact with the pistor
You must adhere to the following waiting periods after installing the camshaft and before cranking the engine back to the TDC position.
- Room temperature (20°C) 4 min.
- 1O°C to 20°C 11 min.
- 0°C to 10°C 30 min..
Pull timing chain up and feed in exhaust camshaft.
Rest timing chain on exhaust camshaft.
Install camshafts with tips on intake and exhaust valves pointing towards 1st cylinder.
Fit bearing cover.
Note: The bearing covers are clearly marked and can be read from the exhaust end:
A1 to A7 for the exhaust end
E1 to E7 for the intake end
Fit special tool 11 3 260 to cylinder head and screw into spark plug threads in cylinders 1 and 4.
Tightening Torque, refer to Engine, Specifications, Mechanical.
Turn the eccentric shaft to pre-tension the bearing caps. Tighten down bearing cover.
Tightening Torque, refer to Engine, Specifications, Mechanical.
Remove special tool 11 3 260.
Caution:
^ Do not damage the cylinder head.
^ Machine open-end wrench accordingly if necessary.
^ Align camshafts with open-end wrench.
Fit special tool 11 3 240 to camshafts on cylinder 6. Align camshafts until special tool 11 3 240 locates on cylinder head without gap.
Attach special tool 11 3 244 to special tool 11 3 240 and locate by way of spark plug thread.
Lift timing chain and hold under tension.
Rotate engine from the 30° before TDC position engine-wise up to TDC position.
Secure crankshaft in TDC position with special tool 11 2 300.
Caution: Remove special tool 11 2 300 before starting engine.
Fit sensor gear to the intake camshaft.
Fit thrust washer and tighten down with dowels.
Tightening Torque, refer to Engine, Specifications, Mechanical.
Feed chain wheel onto timing chain so that arrow on chain wheel faces separating face of upper side of cylinder head.
Insert special tool 11 4 220 in cylinder head and bring adjustment screw into contact with tensioning rail, but do not pretension timing chain yet.
Check that arrow on chain wheel faces separating face of upper side of cylinder head, reposition chain wheel if necessary.
Insert and tighten down screw-in pin.
Tightening Torque, refer to Engine, Specifications, Mechanical.
Install secondary chain tensioner.
Fit toothed sleeve (6) and align in camshaft towards toothed shaft so that the tooth gaps overlap.
Secure toothed shaft (5).
Insert pin of toothed shaft (5) into tooth gaps of splines on camshaft and toothed sleeve (6).
Push in toothed shaft (5) until the longitudinal holes in the toothed sleeve (6) are positioned centrally with respect to the thread.
Place chain wheels in special tool 11 6 180, position tooth gap on inlet chain wheel as shown in illustration and feed on chain.
Caution: Do not alter position of chain wheels with respect to chain when removing from special tool 11 6 180.
Remove chain with chain wheels in position from special tool 11 6 180 and fit so that the tooth gaps on the inlet side are opposed.
Align chain with chain wheels so that the tooth gaps on the inlet side overlap exactly.
Secure toothed shaft (4).
Insert pin of toothed shaft (4) into tooth gaps of splines on camshaft and chain wheel.
Push in toothed shaft (4) until approx. 1 mm of splines can still be seen.
Make sure corrugated washer (7) is installed in correct position; the lettering "FRONT" must be visible.
Install corrugated washer, tighten nuts by hand, do not tighten down fully yet.
Insert screws on exhaust side, initially tighten to approx. 5 Nm and then release again by half a turn.
Fit thrust washer (3).
Pay special attention to the direction of installation of the dished washer (2); lettering "F" must be visible.
Note: If lettering "F" is not visible on a run in engine:
Install cup spring (2) so that small locating diameter of sup spring (2) points to sensor gear.
Fit cup spring (2) in position.
Fit sensor gear (1) so that arrow on sensor gear faces separating face of upper side of cylinder head.
Install nuts and tighten by hand, do not tighten down fully yet.
Withdraw toothed shaft (5) up to stop.
Press down secondary chain tensioner at top and remove special tool 11 3 292.
Preload tensioning rail cover with special tool 11 4 220 by rotating the adjusting screw with special tool 00 9 250 or standard torque wrench to 0.7 Nm.
Preload cup spring slightly by pressing on sensor gear (1) and tighten nuts by hand.
Caution: Do not tighten down nuts fully.
Remove gasket.
Pay attention to adapter sleeves (1).
Keep sealing face clean and free of oil.
Caution:
^ The special tool 11 6 150 may only be attached "without the gasket".
^ If the gasket remains underneath the special tool 11 6 150, the camshaft timing will be "incorrectly" set.
Attach special tool 11 6 150 "without gasket", tighten nuts by hand and then tighten down uniformly until special tool 11 6 150 is in full contact with cylinder head.
Bring screws (1) on exhaust side into contact by initially tightening( to approx. 5 Nm.
Bring nuts (2) on exhaust side and nuts (3) on inlet side into contact by initially tightening to approx. 5 Nm.
Tighten down screws (1) on exhaust side.
Tightening Torque, refer to Engine, Specifications, Mechanical.
Tighten down nuts (2) on exhaust side and nuts (3) on inlet side.
Tightening Torque, refer to Engine, Specifications, Mechanical.
Pull back special tool 11 2 300 until flywheel is no longer located in position.
Remove special tools 11 3 244 and 11 3 240.
Rotate engine twice in direction of rotation until cam tips on inlet and exhaust camshafts on 1st cylinder face one another.
Secure crankshaft in TDC position with special tool 11 2 300.
Caution:
^ Do not turn the engine back.
^ Remove special tool 11 2 300 before starting engine.
Apply special tool 11 3 240 on camshafts.
Note:
^ Due to the rubberized chain wheel, tolerances, and running clearances in the splines, the special tool 11 3 240 can protrude up to 1 mm above the inlet side in spite of the camshafts being correctly set.
^ If the special tool 11 3 240 protrudes above the exhaust side, it will be necessary to readjust the timing.
Remove special tool 11 6 150.
Install VANOS adjustment unit.
Assemble engine.