Replacing the cylinder head (BMW X5 E53)

One of the most common reasons for removing the engine cylinder head is damage to the sealing gasket between the head and the cylinder block. Signs of damage include:

• loss of power;
• coolant level drop;
• oil level drop;
• presence of coolant in oil;
• presence of oil in the coolant;
• foaming of coolant;
• lack of compression in adjacent cylinders.

Replacing the sealing gasket on any of the cylinder heads involves three steps: removing the cylinder head, replacing the sealing gasket, and installing the cylinder head. They are described separately for the right and left heads. If it is necessary to replace the sealing gaskets on both heads, start work with the left cylinder head.

Replacing the left cylinder head

Caution! To remove the exhaust manifolds, it is necessary to fix the engine in the installation position using the "00.0.200" tool, and then lower the front axle beam.

Removal of the left cylinder head must be carried out in the following order.

Prepare the "00.9.120" device. Lower the front axle beam and remove the left exhaust manifold. Temporarily install the front axle beam back in its original place and remove the device for fixing the engine in the installation position.

Remove the coolant drain plug from the left side of the cylinder block. Drain the coolant and dispose of it.

Remove the ignition coils of cylinders 5–8. Remove the left eccentric shaft drive motor and the left cylinder head cover (see above).

Remove the intake air duct (manifold) and the left timing belt cover. Disconnect the SHS and move the engine wiring harness to the side. Unscrew the spark plugs of cylinders 5 - 8. Remove the vent hose from the cylinder head.



Disconnect the hose (1, Fig. 5.48) from the shut-off valve (2). Do not remove the guide tube (3) of the oil dipstick.

Remove the left VANOS intake and exhaust actuators from the cylinder head.



Loosen the bolts (arrows, Fig. 5.49) and remove the eccentric shaft position sensor (2).



Disconnect the chain guide from the cylinder head. Unscrew the bolts (arrows, Fig. 5.50) fastening the timing belt cover to the cylinder head.



Loosen the cylinder head mounting bolts in sequence 10–1 (Fig. 5.51). Unscrew the bolts, remove the cylinder head and its sealing gasket.

Caution! Do not use the removed bolts and cylinder block gasket again to install the cylinder head.

Installation of the cylinder head must be carried out in the following order.

Clean the seals (docking) surfaces on the timing belt cover, cylinder head and engine block, using only a hardwood scraper for this purpose (oak, hornbeam, beech). In doing so, ensure that no sealant residue gets into the air, oil and coolant supply channels.

Blow compressed air through the threaded holes in the cylinder block and cylinder head of the engine to remove traces of liquid (oil). The presence of liquid leads to cracks and incorrect determination of the tightening torque of the bolts.

Apply a sealing compound such as Drei Bond 1209 to the junction of the cylinder head and timing cover (arrows, Fig. 5.52).



Check the centering bushings (1, Fig. 5.53) for damage and correct installation. Replace the cylinder head gasket by installing it on the centering bushings.

Attention! For the cylinder head with sealing surface treatment, install a thicker (0.3 mm) sealing gasket.

Do not lubricate the surface of the new cylinder head bolts, and do not wash off the coating. Insert the new cylinder head bolts and tighten them by hand, crosswise, in order 1–10 (see fig. 5.51).

Using a pressure wrench and the "00.9.120" tool, tighten the new cylinder head mounting bolts (M10) in sequence 1–10 (Fig. 5.51) in three successive steps:

• Step 1 – tighten to 30 Nm (3.0 kgf·m);
• 2nd step – turn it to an angle of 90°;
• 3rd step – turn it at an angle of 90°.

Insert and tighten the timing belt cover to cylinder head bolts (arrows, see Fig. 5.50).

Install the chain guide mounting bolt and tighten it.

Install the eccentric shaft sensor (2) (see fig. 5.49). Install the left VANOS intake and exhaust actuators.

Assemble the engine, replacing the gasket of the bolt (M14x1.5) of the drain hole of the engine block, and tighten it to a torque of 25 N·m (2.5 kgf·m). Fill with coolant. Bleed the cooling system and check it for leaks.

Replacing the right cylinder head

Attention! To remove the exhaust manifolds, it is necessary to fix the engine in the installation position using the device "00.9.120" and then lower the front axle beam.

Removal of the left cylinder head must be carried out in the following order.

Prepare the device "00.9.120", lower the front axle beam. Remove the right exhaust manifold and temporarily install the front axle beam back in its original place. Remove the device for fixing the engine in the installation position.

Unscrew the coolant drain plug on the left side of the cylinder block. Drain it and send it for disposal. Remove the ignition coils of cylinders 1–4. Remove the right eccentric shaft drive motor.

Remove the right cylinder head cover and remove the intake air duct (manifold). Remove the right timing belt cover, disconnect the spark plugs and move the engine wiring harness to the side. Unscrew the spark plugs of cylinders 1–4. Remove the vent hose from the cylinder head.

Disconnect the hose (1, Fig. 5.54) from the shut-off valve (2). A spacer sleeve is secured behind the pipe (5) with a bolt (3). Unscrew the bolt (3) and remove the shut-off valve (4), pipe (5) and spacer sleeve.



Remove the right-hand VANOS intake and exhaust actuators from the cylinder head.

Loosen the plunger (Fig. 5.55) of the chain tensioner by 1–1.5 turns.





Loosen the bolts and remove the eccentric shaft position sensor. Disconnect the chain guide from the cylinder head. Loosen the bolts (arrows, Fig. 5.56) fastening the timing belt cover to the cylinder head.



Loosen the cylinder head mounting bolts in sequence 10–1 (Fig. 5.57) by one turn and unscrew the bolts.

Caution! Do not use the removed bolts and cylinder block gasket again to install the cylinder head.

Remove the cylinder head. Remove the cylinder head gasket. Remove the chain tensioner plunger. Install the plunger (1, Fig. 5.58) chain tensioner onto a flat surface and slowly and carefully squeeze. Repeat the process twice.



The installation of the cylinder head must be carried out in the same order as for the left cylinder head, while it is necessary.

Replace the tensioner plunger sealing ring. Install the plunger (1) and tighten it until the mounting bolt heads touch.

Apply a sealing compound such as Drei Bond 1209 to the junction of the cylinder head and timing cover (arrows, Fig. 5.59).



Check the centering bushings (1, Fig. 5.60) for the absence of damage and for their correct installation.



Replace the cylinder head gasket by installing it on the centering bushings.

Attention! For the cylinder head with sealing surface treatment, install a thicker (0.3 mm) sealing gasket.

Insert and tighten the timing belt cover to cylinder head bolts (arrows, see Fig. 5.56).

Install the chain guide mounting bolt (arrow, Fig. 5.61) and tighten it.



Tighten the plunger (1, M22x1.5; see Fig. 5.55) chain tensioner with a torque of 65 N·m (6.5 kgf·m).

Install the right-hand VANOS intake and exhaust control units.

Assemble the engine, replacing the gasket of the bolt (M14x1.5) of the drain hole of the engine block and tightening it to a torque of 25 N·m (2.5 kgf·m). Fill with coolant. Bleed the cooling system and check it for leaks.