Replacing the lower timing belt cover (BMW X5 E53)

The design of the lower timing belt cover is shown in Fig. 3.77.



The replacement of the lower timing belt cover must be carried out in the following order: Remove the D-VANOS system actuator and thermostat.

Remove the alternator drive belt and its tensioner. Hold the coolant pump pulley from turning with the drive belt and unscrew the pulley mounting bolts.

Remove the vibration damper. When the vibration damper is designed with a separate hub, it is necessary to remove the vibration damper hub. Remove the oil pan.

Using a mandrel with a diameter of less than 5.0 mm, press out the centering pins (3) on the timing belt cover, moving backwards. Unscrew the upper bolts (arrows, Fig. 3.78) fastening the timing belt cover to the cylinder head.



Remove the bolts (arrows, Fig. 3.79)fastening the timing belt cover to the cylinder block and remove it from the end of the engine.

Caution! Check the cylinder head gasket for damage. If necessary, remove the cylinder head and replace its gasket.

Clean the sealing surfaces on the timing belt cover and cylinder head using a hardwood scraper.

Drive in cylindrical pins (3, Fig. 3.77) into the timing belt cover so that they protrude by approximately 2-3 mm.

Secure the new seals (5 and 6) to the timing belt cover with a small amount of grease. Apply a bead of sealant such as "Drei Bond 1209" at the junction of the timing belt cover and cylinder head sealing gaskets.

Install the timing belt cover and tighten all bolts (arrows, Fig. 3.79) its fastening to the cylinder block. Pre-tighten the bolts to a torque of 5 N·m (0.5 kgf·m).

Simultaneously, firmly insert the centering pins (3. see fig. 3.77).

Tighten all bolts (M8, Fig. 3.79) fastening the timing belt cover to the cylinder block in a staggered pattern with a torque of 10 N·m (1.0 kgf·m).

Attention! When all the bolts are tightened, to check, tighten them again in a checkerboard pattern with a tightening torque of 10 N·m (1.0 kgf·m).

Screw in the bolts (arrows, see Fig. 3.78) fastening the timing belt cover to the cylinder head and tighten them to a torque of 10 N·m (1.0 kgf·m).

Replace the front crankshaft oil seal and reassemble the engine.