Removal and installation timing chain covers (BMW 7 Series E38)

Upper chain covers and camshaft sprockets

Removal

1. Remove the cylinder head covers (see section Engine M62).

2. Remove the cooling system fan drive coupling with the impeller and fan housing.

3. On cylinder block No.1-6, remove the shut-off valve.

4. Remove the housings of both ignition distributors (see chapter Fuel and exhaust systems).

5. Remove the CMP sensor if necessary.



6. Remove the oil pan guide mounting bolt.



7. Remove the oil filler cap and unscrew the bolt.

8. Loosen the mounting bolts and remove the upper front timing chain cover.







9. Remove the camshaft drive chain guide.

10. Turn the crankshaft clockwise by the central bolt until the piston of the first cylinder is at TDC at the end of the compression stroke.

In this position, the notch (1) on the camshaft flange must be in line with the fuel distribution line mounting bolt (2).

11. Remove the dust cover from the crankshaft locking hole and lock the shaft using tool No.11 2 300 or a suitable rod.





12. Secure both camshafts using tool No.11 3 190.

The crankshaft and camshafts must remain in a fixed position until the end of the work.

13. Press the tensioner protective cap with a screwdriver, loosen the lock nut (2) located by the cap, turn the adjusting bolt (1) a few turns. Carefully loosen the cap nut (3).

The nut (3) is spring loaded.

14. Unscrew the bolts securing the left and right sprockets, then secure the chain so that it does not slip.



15. Loosen the bolt (1) securing the chain guide bar. Pull the guide bar out of the lower fastening loop in an upward motion.



16. Unscrew the bolts (1) and remove the upper rear timing chain cover.

Installation

1. Clean the mating surfaces from dirt and grease.

2. Make sure that the centering bushings are intact and installed correctly.



3. Install new gaskets (1) on both rows of cylinders. On the gaskets (1 Apply Hylomar SQ 32 M sealant around the chain hole).



5. Install the rear cover and tighten all bolts by hand. Tighten the bolts securing the rear cover to the lower cover first, then to the cylinder heads with the required force.

6. Before installing the camshaft sprocket for cylinder bank No.7-12, do not forget to install the CMP sensor rotor on the protrusion on the shaft.

7. Install the sprockets on the camshafts, aligning the longitudinal holes in the center; tighten the sprocket mounting bolts by hand.



8. Install the chain tensioner plunger so that the guide lug (1) fits into the tensioner bar. Insert the spring and tighten the screw plug (2).



9. Adjust the chain tension. To do this, press and pull the tensioner bar in the direction of the drive chain and measure the distance A. Press the tensioner bar back to the stop, measure the distance B and subtract the distance A from it. Use the adjusting screw to set the specified value (6 + 0.5 mm) and tighten the lock nut.



10. Install the new tensioner protective cap.

11. Tighten the camshaft sprocket mounting bolts to the required torque: first on the side of cylinders No.7-12, then on the side of cylinders No.1-6.

12. Install the camshaft timing chain guide.



13. Insert the chain guide bar from above and fix it in the mounting plate. Tighten the chain guide mounting bolt.

When the timing belt cover is installed, the mounting loop is not visible.

14. Clean the mating surfaces of the chain cover from dirt and oil. Check the cover centering bushings for damage and correct installation. Apply Hylomar SQ 32 M sealant to the joint surfaces of the upper and lower covers.

15. Install new sealing gaskets so that the sealing strip faces outward.

16. Install the upper front timing belt cover.

17. Hand tighten the bolt in the oil filler pipe and the bolt securing the oil pan guide.

18. Tighten the upper front timing chain cover mounting bolts.

19. Install the other removed components in the reverse order of their removal.

Lower front cover

1. Drain the engine cooling system (see chapter Vehicle settings and routine maintenance).

2. Remove the upper timing chain covers and the upper section of the oil pan (see section Removal and installation the upper section of the oil pan and oil pump).



3. Loosen the clamp and disconnect the hose.



4. Unscrew the bolts and remove the bracket, move the hose to the side. Remove the torsional vibration damper.



5. Remove the bolts securing the lower front timing chain cover.

6. Fix the timing chain and its bars. Clean the sealing surfaces of the engine crankcase, check the correct position of the centering bushings.

7. Install new sealing gaskets. Apply a layer of Hylomar SQ 32 M sealant to the joint surfaces of the timing chain cover gaskets.

8. Replace the front crankshaft oil seal (see section Replacing crankshaft seals and distributor seals).

9. Connect the removed hoses.

Lower back cover

1. Remove the lower front timing chain cover.



2. Unscrew the water pump mounting bolts and remove it.



3. Remove the snap ring, tensioner bar and timing chain.



4. Remove the tensioner bar stop bolt (1). If necessary, remove the chain guide bar mounting bracket (2).

5. Unscrew the mounting bolts. Remove the lower rear timing belt cover.

6. Installation is done in reverse order. Use a new timing chain cover gasket; apply Hylomar SQ 32 M sealant to the joint surface. Replace the water pump gasket.