bmwrepairs: July 2011

Remove the cylinder head.
NOTE
Special tools are required to perform this operation. BMW tools 11-3-260/270/250 or equivalent are required for proper removal and installation of the camshafts and for retention of the valve lash compensators. Without these tools the camshafts will be damaged during removal or installation.

Remove the spark plugs and attach the 11-3-260 (plus addition 11-3-270) camshaft removal fixture. Torque the hold down bolts in the spark plug bores to 17 ft. lbs. (23 Nm).

Apply load to the bearing caps by rotating the eccentric shaft. This relieves the tension on the bearing cap bolts. Loosen and remove the bearing cap bolts.

Remove the camshaft removal fixture after releasing the tension from the eccentric shaft.

Remove the camshafts and the bearing caps. Note that the intake camshaft is marked "E" and the exhaust camshaft is marked "A". The camshaft bearing are consecutively numbered with "A" or "E" to designate intake or exhaust side.

Hold the valve lash compensators in place using tool 11-3-250 or equivalent, and remove the bearing plate along with the valve plungers.

To install:

Inspect the camshafts and valve lash compensators for damage and wear and replace as necessary.

Install the camshafts with the cylinder number 1 intake and exhaust cam peaks pointing at each other. The flats on the sprocket ends of the camshafts should be parallel. The exhaust camshaft is marked with a notch on the flange.

Install the fixture. Place the bearing caps into position and press the caps down with the tool. Torque the bolts to 10-12 ft. lbs. (13-17 Nm).

When the camshafts have been removed and reinstalled a waiting period dependent on the ambient temperature is necessary before mounting the cylinder head on the engine. At room temperature wait 4 minutes to allow the lifters to compress fully. At temperatures down to 50° F(10° C) wait 11 minutes. At temperatures lower than 50° F(10° C) wait 30 minutes. This is to prevent contact between the valves and the piston tops.

The engine may not be cranked under the same conditions as above for a period of 10 minutes at room temperature; 30 minutes for temperatures down to 50° F(10° C); 75 minutes for temperatures below 50° F(10° C).

M52 2.5L, 2.8L, & S52 3.2L Engines

Fig. Camshaft removal tools 11-3-260 and 11-3-270 used to hold the camshaft journals in place during camshaft removal-M52 2.5L, 2.8L, S52 3.2L engines

Fig. Camshaft bearing journal bolt locations-M52 2.5L, 2.8L, S52 3.2L engines

Fig. Bearing cap ID markings. The intake camshaft journals are indicated by the letter E, the exhaust journals are indicated by the letter A-M52 2.5L, 2.8L, and S52 3.2L engines

Fig. Check the bore surfaces of the valve clearance compensators for scoring-M52 2.5L, 2.8L, and S52 3.2L engines

Fig. The lower camshaft journal and tappet bore assemblies are marked A for exhaust and E for intake-M52 2.5L, 2.8L, S52 3.2L engines

Before servicing the vehicle, refer to the precautions in the beginning of this section.

Remove or disconnect the following:
NOTE
There are several tools recommended for removing the camshafts. Without these tools there is a risk the camshaft could break during removal, or damage to a valve could occur.

Fuel pressure
Negative battery cable
Cylinder head, if necessary. If the fresh air intake shroud on the firewall is removable, removing the shroud should allow enough room to remove the camshafts. If the body of the vehicle interferes with the camshaft removal, removing the cylinder head is necessary

Rear hood seal, then remove the fasteners securing the sealed plastic housing for the engine wiring harness from the passenger compartment fresh air intake shroud
Fasteners securing the fresh air intake shroud to the firewall, and remove the shroud
If equipped, plastic trim covers from the top of the engine
Wire connectors for the ignition coils and cylinder head sensors and remove the coils, then remove the cylinder head cover

Rotate the engine in the direction of rotation to TDC for cylinder number one. Cylinder number 1 will be at TDC when the intake and exhaust camshaft peaks for cylinder number 1 face each other

Lock the engine in the TDC position by placing the holding dowel tool No. 11-2-300 through the machined hole in the engine block, just inside of the transmission bell housing mounting tab located on the left lower portion of the engine block. Slide the locating dowel through the machined hole in the block and into the machined hole in the flywheel to prevent movement of the crankshaft.

The camshafts are held in the TDC position by placing tool No. 11-3-240 on the valve cover mating surface at the back of the cylinder head and onto the squared ends of the camshafts, securing the camshafts such that 2 sides of the squared ends are parallel with the cam cover gasket mating surface. With the camshafts in this position, the arrows on the sprockets will be facing up.

Remove or disconnect the following:

Valve cover mounting studs
2 hex plugs at the front of the cylinder head to access the exhaust camshaft sprocket mounting bolts, then loosen the exhaust cam sprocket bolts 2 turns

Press down on the secondary cam chain tensioner between the 2 camshaft sprockets and install tool No. 11-3-292 through the back side of the tensioner housing to hold the tensioner down. A similar sized and suitably hardened drill bit can be substituted for tool No. 11-3-292.

Remove the fasteners from the front of the cylinder head securing the hydraulic variable camshaft control (VANOS) unit to the cylinder head, and inspect to make sure any hydraulic or sensor connectors have been removed or disconnected.

On engines with a spring plate installed on the intake camshaft, place tool No. 11-5-490 onto the exhaust camshaft sprocket and carefully rotate the sprocket clockwise to allow the helical gear of the VANOS unit to release the intake camshaft and to allow the VANOS unit to be pulled away from the front of the cylinder head.

If tool No. 11-5-490 is not available, move the camshaft sprockets to release the VANOS by using a suitable drift and soft faced mallet and lightly tapping on a sprocket tooth of the intake cam sprocket to rotate both cam sprockets clockwise, while alternately pulling on the VANOS unit to release it. This procedure may need to be repeated several times to fully release the VANOS unit, and must be performed very carefully, in such a manner to not distort or damage the teeth of the cam sprocket.

With the VANOS assembly removed, remove the intake and exhaust camshaft sprockets, the hydraulic cam chain tensioner, and the cam chain guide.

From the side of the right front area of the engine, remove the cap nut for the cam chain tensioner for the cam chain that runs between the crankshaft and the exhaust camshaft sprocket. Use care when removing the tensioner cap nut as the cam tensioner spring applies pressure to the cap nut.

Remove the exhaust cam tensioner, and then release the sprocket from the cam chain.

Attach a wire tie or mechanic-s wire to the cam chain and temporarily secure the chain fully extended.

Remove the dowel from the engine and flywheel locking the engine in the TDC position.

While holding the crankshaft to exhaust camshaft cam chain, rotate the engine 30 degrees counterclockwise to avoid damaging the valves during camshaft removal and reinstallation.

With the attached wire tie or mechanic-s wire secured to the cam chain, and carefully lower the chain downward making sure there is enough exposed wire to retrieve the chain for reinstallation.

Remove the spark plugs and install the upper camshaft journal holding device, tool No. 11-3-260/270/250. Tighten the hold down bolts in the spark plug bores to 17 ft. lbs. (23 Nm).

Apply a load to the bearing caps by rotating the eccentric shaft. This relieves the tension on the bearing cap bolts. Loosen and remove the bearing cap bolts.

Slowly and carefully rotate the eccentric of the cam cap holding fixture to release the camshaft.

Remove and rotate the camshaft fixture tool 180 degrees and repeat the above procedures to remove the other camshaft.

Remove the camshafts and the bearing caps. Note that the intake camshaft is marked E and the exhaust camshaft is marked A . The camshaft bearing are consecutively numbered and lettered with A or E to designate intake or exhaust side.

Hold the valve lash compensators in place using tool 11-3-250 and remove the bearing plate along with the valve plungers.

To install:

Apply fresh engine oil to the camshaft journals and lobes.

Place the camshaft in cam journals of the cylinder head.

Place the upper camshaft journal bearing caps on the camshaft in the correct order. Note that the intake camshaft is marked E and the exhaust camshaft is marked A . The camshaft bearing are consecutively numbered and lettered with A or E to designate intake or exhaust side.

With the spark plugs removed install the upper camshaft journal holding device, tool No. 11-3-260/270/250. Tighten the hold down bolts in the spark plug bores to 17 ft. lbs. (23 Nm).

Rotate the eccentric shaft of the camshaft journal holding fixture to seat the camshaft and journals into the cylinder head.

Use the holding fixture to secure the camshaft journals and camshaft into the cylinder head Install the camshaft journal bolts and torque as follows:

M6 fasteners: 89 inch lbs. (10 Nm)
M7 fasteners: 10 ft. lbs. (14 Nm)
M8 fasteners: 14 ft. lbs. (19 Nm)

Repeat the above procedures to install the second camshaft.

Remove the camshaft journal fixture tool.

Align the camshafts so that lobes of the intake and exhaust cams face each other for the No. 1 cylinder. The camshafts can be turned on the hexagon casting using a 1 ¹ / ₁₆ inch or 27mm open end wrench.
NOTE
Once the camshafts have been removed and reinstalled a waiting period dependent on the ambient temperature is necessary before rotating the engine. At room temperature wait 4 minutes to allow the lifters to compress fully. At temperatures down to 50°F (10°C) wait 11 minutes. At temperatures lower than 50°F (10°C) wait 30 minutes. This is to prevent contact between the valves and the piston tops. The engine may not be cranked under the same condition for a period of 10 minutes at room temperature; 30 minutes for temperatures down to 50°F (10°C); 75 minutes for temperatures below 50°F (10°C).

With the attached wire secured to the crankshaft cam chain, carefully raise the chain upward and apply a light tension to the chain, then while holding the chain, carefully rotate the engine clockwise to TDC on cylinder number one.

Lock the engine in the TDC position by placing the holding dowel tool No. 11-2-300 through the machined hole in the engine block, just inside of the transmission bell housing mounting tab located on the left lower portion of the engine block. Slide the locating dowel through the machined hole in the block and into the machined hole in the flywheel to prevent movement of the crankshaft.

Hold the camshafts TDC position by placing tool No. 11-3-240 on the valve cover mating surface at the back of the cylinder head and onto the squared ends of the camshafts, securing the camshafts such that 2 sides of the squared ends are parallel with the cam cover gasket mating surface. With the camshafts in this position, the arrows on the sprockets will be facing up.

Position the crankshaft cam chain over the exhaust cam chain sprocket and install the sprocket on the exhaust cam such that the slotted holes are centered with the fastener bores in the camshaft.

Install the hydraulic cam chain tensioner, and the cam chain guide, then the intake and exhaust camshaft sprockets along with the cam chain and remove the tool used to hold the hydraulic cam chain tensioner collapsed.

Install the crankshaft cam chain tensioner assembly, spring and cap nut.

Apply sealant to the upper corners of the cylinder head where the VANOS housing mounts and install a new VANOS housing gasket.

Press the helical gear of the VANOS assembly toward the housing and install the VANOS assembly. To do so on engines with a spring plate installed on the intake camshaft, place tool No. 11-5-490 onto the exhaust camshaft sprocket and carefully rotate the sprocket counterclockwise to allow the helical gear of the VANOS unit to thread into the intake camshaft and to allow the VANOS unit to be pulled into the front of the cylinder head.

If tool No. 11-5-490 is not available, move the camshaft sprockets to install the VANOS by using a suitable drift and soft faced mallet and lightly tapping on a sprocket tooth of the exhaust cam sprocket to rotate both cam sprockets counterclockwise, while alternately pressing on the VANOS unit to install it. This procedure may need to be repeated several times to fully install the VANOS unit, and must be performed very carefully, in such a manner to not distort or damage the teeth of the cam sprocket.
NOTE
Make sure when assembling the VANOS unit is able to rest on the front of the cylinder head without being forced or without binding. If the VANOS unit does not fully seat it may be necessary to reposition the camshaft sprockets such that the slots in the camshaft sprockets allow enough movement of the sprockets for the helical gear of the VANOS assembly to be fully seated during assembly.

Tighten the VANOS unit fastener and then torque the camshaft sprocket bolts of both the intake and exhaust cams to 16 ft. lbs. (22 Nm).

Remove the crankshaft TDC holding dowel tool No. 11-3-240 from the engine, and remove the camshaft TDC positioning tool No. 11-3-240 from the valve cover mating surface at the back of the cylinder head.

Slowly and carefully rotate the engine clockwise 4 complete revolutions bringing cylinder number 1 to TDC. If the engine binds for any reason stop immediately to evaluate and rectify the cause of the binding.

With cylinder number 1 at TDC slide the camshaft TDC positioning tool No. 11-3-240 over the ends of the cams and onto the valve cover mating surface. If the tool slides over the cams and is flush with the mating surface, the camshafts are properly timed. If the tool does not slide easily over the ends of the cams, or if the tool is not flush with the valve cover mating surface, the camshaft timing must be repeated until the tool fits squarely.

The balance of the assembly is in reverse order of disassembly.

Check all fluid levels as necessary.

Connect the negative battery cable.

M54 And S54 Engines

Fig. Camshaft removal tools 11-3-260 and 11-3-270 used to hold the camshaft journals in place during camshaft removal

Fig. Camshaft bearing journal bolt locations

Fig. Bearing cap ID markings. The intake camshaft journals are indicated by the letter E, the exhaust journals are indicated by the letter A

Fig. Check the bore surfaces of the valve clearance compensators for scoring

Fig. The lower camshaft journal and tappet bore assemblies are marked A for exhaust and E for intake

Before servicing the vehicle, refer to the Precautions section.

Remove or disconnect the following:

Fuel pressure
Negative battery cable
Cylinder head, if necessary. If the fresh air intake shroud on the firewall is removable, removing the shroud should allow enough room to remove the camshafts. If the body of the vehicle interferes with the camshaft removal, removing the cylinder head is necessary

NOTE

There are several tools recommended for removing the camshafts. Without these tools there is a risk the camshaft could break during removal, or damage to a valve could occur.

Rear hood seal, then remove the fasteners securing the sealed plastic housing for the engine wiring harness from the passenger compartment fresh air intake shroud.

Fasteners securing the fresh air intake shroud to the firewall, and remove the shroud

If equipped, plastic trim covers from the top of the engine

Wire connectors for the ignition coils and cylinder head sensors and remove the coils, then remove the cylinder head cover

Rotate the engine in the direction of rotation to TDC for cylinder number one. Cylinder number 1 will be at Top Dead center (TDC) when the intake and exhaust camshaft peaks for cylinder number 1 face each other

Lock the engine in the TDC position by placing the holding dowel tool No. 11-2-300 through the machined hole in the engine block, just inside of the transmission bell housing mounting tab located on the left lower portion of the engine block. Slide the locating dowel through the machined hole in the block and into the machined hole in the flywheel to prevent movement of the crankshaft.

The camshafts are held in the TDC position by placing tool No. 11-3-240 on the valve cover mating surface at the back of the cylinder head and onto the squared ends of the camshafts, securing the camshafts such that 2 sides of the squared ends are parallel with the cam cover gasket mating surface. With the camshafts in this position, the arrows on the sprockets will be facing up.

Remove or disconnect the following:

Valve cover mounting studs
2 hex plugs at the front of the cylinder head to access the exhaust camshaft sprocket mounting bolts, then loosen the exhaust cam sprocket bolts 2 turns

Press down on the secondary cam chain tensioner between the 2 camshaft sprockets and install tool No. 11-3-292 through the back side of the tensioner housing to hold the tensioner down. A similar sized and suitably hardened drill bit can be substituted for tool No. 11-3-292.

Remove the fasteners from the front of the cylinder head securing the hydraulic variable camshaft control (VANOS) unit to the cylinder head, and inspect to make sure any hydraulic or sensor connectors have been removed or disconnected.

On engines with a spring plate installed on the intake camshaft, place tool No. 11-5-490 onto the exhaust camshaft sprocket and carefully rotate the sprocket clockwise to allow the helical gear of the VANOS unit to release the intake camshaft and to allow the VANOS unit to be pulled away from the front of the cylinder head.

If tool No. 11-5-490 is not available, move the camshaft sprockets to release the VANOS by using a suitable drift and soft faced mallet and lightly tapping on a sprocket tooth of the intake cam sprocket to rotate both cam sprockets clockwise, while alternately pulling on the VANOS unit to release it. This procedure may need to be repeated several times to fully release the VANOS unit, and must be performed very carefully, in such a manner to not distort or damage the teeth of the cam sprocket.

With the VANOS assembly removed, remove the intake and exhaust camshaft sprockets, the hydraulic cam chain tensioner, and the cam chain guide.

From the side of the right front area of the engine, remove the cap nut for the cam chain tensioner for the cam chain that runs between the crankshaft and the exhaust camshaft sprocket. Use care when removing the tensioner cap nut as the cam tensioner spring applies pressure to the cap nut.

Remove the exhaust cam tensioner, and then release the sprocket from the cam chain.

Attach a wire tie or mechanics wire to the cam chain and temporarily secure the chain fully extended.

Remove the dowel from the engine and flywheel locking the engine in the TDC position.

While holding the crankshaft to exhaust camshaft cam chain, rotate the engine 30 degrees counterclockwise to avoid damaging the valves during camshaft removal and reinstallation.

With the attached wire tie or mechanic-s wire secured to the cam chain, and carefully lower the chain downward making sure there is enough exposed wire to retrieve the chain for reinstallation.

Remove the spark plugs and install the upper camshaft journal holding device, tool No. 11-3-260/270/250. Tighten the hold down bolts in the spark plug bores to 17 ft. lbs. (23 Nm).

Apply a load to the bearing caps by rotating the eccentric shaft. This relieves the tension on the bearing cap bolts. Loosen and remove the bearing cap bolts.

Slowly and carefully rotate the eccentric of the cam cap holding fixture to release the camshaft.

Remove and rotate the camshaft fixture tool 180 degrees and repeat the above procedures to remove the other camshaft.

Remove the camshafts and the bearing caps. Note that the intake camshaft is markedEAAE

Hold the valve lash compensators in place using tool 11-3-250 and remove the bearing plate along with the valve plungers.

To install:

Apply fresh engine oil to the camshaft journals and lobes.

Place the camshaft in cam journals of the cylinder head.

Place the upper camshaft journal bearing caps on the camshaft in the correct order. Note that the intake camshaft is markedEAAE

With the spark plugs removed install the upper camshaft journal holding device, tool No. 11-3-260/270/250. Tighten the hold down bolts in the spark plug bores to 17 ft. lbs. (23 Nm).

Rotate the eccentric shaft of the camshaft journal holding fixture to seat the camshaft and journals into the cylinder head.

Use the holding fixture to secure the camshaft journals and camshaft into the cylinder head Install the camshaft journal bolts and torque as follows:

M6 fasteners: 89 inch lbs. (10 Nm)
M7 fasteners: 10 ft. lbs. (14 Nm)
M8 fasteners: 14 ft. lbs. (19 Nm)

Repeat the above procedures to install the second camshaft.

Remove the camshaft journal fixture tool.

Align the camshafts so that lobes of the intake and exhaust cams face each other for the No. 1 cylinder. The camshafts can be turned on the hexagon casting using a 1¹₁₆

NOTE

Once the camshafts have been removed and reinstalled a waiting period dependent on the ambient temperature is necessary before rotating the engine. At room temperature wait 4 minutes to allow the lifters to compress fully. At temperatures down to 50°F (10°C) wait 11 minutes. At temperatures lower than 50°F (10°C) wait 30 minutes. This is to prevent contact between the valves and the piston tops. The engine may not be cranked under the same condition for a period of 10 minutes at room temperature; 30 minutes for temperatures down to 50°F (10°C); 75 minutes for temperatures below 50°F (10°C).

With the attached wire secured to the crankshaft cam chain, carefully raise the chain upward and apply a light tension to the chain, then while holding the chain, carefully rotate the engine clockwise to TDC on cylinder number one.

Lock the engine in the TDC position by placing the holding dowel tool No. 11-2-300 through the machined hole in the engine block, just inside of the transmission bell housing mounting tab located on the left lower portion of the engine block. Slide the locating dowel through the machined hole in the block and into the machined hole in the flywheel to prevent movement of the crankshaft.

Hold the camshafts TDC position by placing tool No. 11-3-240 on the valve cover mating surface at the back of the cylinder head and onto the squared ends of the camshafts, securing the camshafts such that 2 sides of the squared ends are parallel with the cam cover gasket mating surface. With the camshafts in this position, the arrows on the sprockets will be facing up.

Position the crankshaft cam chain over the exhaust cam chain sprocket and install the sprocket on the exhaust cam such that the slotted holes are centered with the fastener bores in the camshaft.

Install the hydraulic cam chain tensioner, and the cam chain guide, then the intake and exhaust camshaft sprockets along with the cam chain and remove the tool used to hold the hydraulic cam chain tensioner collapsed.

Install the crankshaft cam chain tensioner assembly, spring and cap nut.

Apply sealant to the upper corners of the cylinder head where the VANOS housing mounts and install a new VANOS housing gasket.

Press the helical gear of the VANOS assembly toward the housing and install the VANOS assembly. To do so on engines with a spring plate installed on the intake camshaft, place tool No. 11-5-490 onto the exhaust camshaft sprocket and carefully rotate the sprocket counterclockwise to allow the helical gear of the VANOS unit to thread into the intake camshaft and to allow the VANOS unit to be pulled into the front of the cylinder head.

If tool No. 11-5-490 is not available, move the camshaft sprockets to install the VANOS by using a suitable drift and soft faced mallet and lightly tapping on a sprocket tooth of the exhaust cam sprocket to rotate both cam sprockets counterclockwise, while alternately pressing on the VANOS unit to install it. This procedure may need to be repeated several times to fully install the VANOS unit, and must be performed very carefully, in such a manner to not distort or damage the teeth of the cam sprocket.

NOTE

Make sure when assembling the VANOS unit is able to rest on the front of the cylinder head without being forced or without binding. If the VANOS unit does not fully seat it may be necessary to reposition the camshaft sprockets such that the slots in the camshaft sprockets allow enough movement of the sprockets for the helical gear of the VANOS assembly to be fully seated during assembly.

Tighten the VANOS unit fastener and then torque the camshaft sprocket bolts of both the intake and exhaust cams to 16 ft. lbs. (22 Nm).

Remove the crankshaft TDC holding dowel tool No. 11-3-240 from the engine, and remove the camshaft TDC positioning tool No. 11-3-240 from the valve cover mating surface at the back of the cylinder head.

Slowly and carefully rotate the engine clockwise 4 complete revolutions bringing cylinder number 1 to TDC. If the engine binds for any reason stop immediately to evaluate and rectify the cause of the binding.

With cylinder number 1 at TDC slide the camshaft TDC positioning tool No. 11-3-240 over the ends of the cams and onto the valve cover mating surface. If the tool slides over the cams and is flush with the mating surface, the camshafts are properly timed. If the tool does not slide easily over the ends of the cams, or if the tool is not flush with the valve cover mating surface, the camshaft timing must be repeated until the tool fits squarely.

The balance of the assembly is in reverse order of disassembly.

Check all fluid levels as necessary.

Connect the negative battery cable.

Fig. Camshaft removal tools 11-3-260 and 11-3-270 used to hold the camshaft journals in place during camshaft removal

Fig. Camshaft bearing journal bolt locations

Fig. Bearing cap ID markings. The intake camshaft journals are indicated by the letter E, the exhaust journals are indicated by the letter A

Fig. Check the bore surfaces of the valve clearance compensators for scoring

Fig. The lower camshaft journal and tappet bore assemblies are marked A for exhaust and E for intake

Before servicing the vehicle, refer to the Precautions section.

Remove or disconnect the following:
NOTE
There are several tools recommended for removing the camshafts. Without these tools there is a risk the camshaft could break during removal, or damage to a valve could occur.

Fuel pressure
Negative battery cable
Cylinder head, if necessary. If the fresh air intake shroud on the firewall is removable, removing the shroud should allow enough room to remove the camshafts. If the body of the vehicle interferes with the camshaft removal, removing the cylinder head is necessary

Rear hood seal, then remove the fasteners securing the sealed plastic housing for the engine wiring harness from the passenger compartment fresh air intake shroud.
Fasteners securing the fresh air intake shroud to the firewall, and remove the shroud
If equipped, plastic trim covers from the top of the engine
Wire connectors for the ignition coils and cylinder head sensors and remove the coils, then remove the cylinder head cover

Rotate the engine in the direction of rotation to TDC for cylinder number one. Cylinder number 1 will be at Top Dead center (TDC) when the intake and exhaust camshaft peaks for cylinder number 1 face each other

Lock the engine in the TDC position by placing the holding dowel tool No. 11-2-300 through the machined hole in the engine block, just inside of the transmission bell housing mounting tab located on the left lower portion of the engine block. Slide the locating dowel through the machined hole in the block and into the machined hole in the flywheel to prevent movement of the crankshaft.

The camshafts are held in the TDC position by placing tool No. 11-3-240 on the valve cover mating surface at the back of the cylinder head and onto the squared ends of the camshafts, securing the camshafts such that 2 sides of the squared ends are parallel with the cam cover gasket mating surface. With the camshafts in this position, the arrows on the sprockets will be facing up.

Remove or disconnect the following:

Valve cover mounting studs
2 hex plugs at the front of the cylinder head to access the exhaust camshaft sprocket mounting bolts, then loosen the exhaust cam sprocket bolts 2 turns

Press down on the secondary cam chain tensioner between the 2 camshaft sprockets and install tool No. 11-3-292 through the back side of the tensioner housing to hold the tensioner down. A similar sized and suitably hardened drill bit can be substituted for tool No. 11-3-292.

Remove the fasteners from the front of the cylinder head securing the hydraulic variable camshaft control (VANOS) unit to the cylinder head, and inspect to make sure any hydraulic or sensor connectors have been removed or disconnected.

On engines with a spring plate installed on the intake camshaft, place tool No. 11-5-490 onto the exhaust camshaft sprocket and carefully rotate the sprocket clockwise to allow the helical gear of the VANOS unit to release the intake camshaft and to allow the VANOS unit to be pulled away from the front of the cylinder head.

If tool No. 11-5-490 is not available, move the camshaft sprockets to release the VANOS by using a suitable drift and soft faced mallet and lightly tapping on a sprocket tooth of the intake cam sprocket to rotate both cam sprockets clockwise, while alternately pulling on the VANOS unit to release it. This procedure may need to be repeated several times to fully release the VANOS unit, and must be performed very carefully, in such a manner to not distort or damage the teeth of the cam sprocket.

With the VANOS assembly removed, remove the intake and exhaust camshaft sprockets, the hydraulic cam chain tensioner, and the cam chain guide.

From the side of the right front area of the engine, remove the cap nut for the cam chain tensioner for the cam chain that runs between the crankshaft and the exhaust camshaft sprocket. Use care when removing the tensioner cap nut as the cam tensioner spring applies pressure to the cap nut.

Remove the exhaust cam tensioner, and then release the sprocket from the cam chain.

Attach a wire tie or mechanic-s wire to the cam chain and temporarily secure the chain fully extended.

Remove the dowel from the engine and flywheel locking the engine in the TDC position.

While holding the crankshaft to exhaust camshaft cam chain, rotate the engine 30 degrees counterclockwise to avoid damaging the valves during camshaft removal and reinstallation.

With the attached wire tie or mechanic-s wire secured to the cam chain, and carefully lower the chain downward making sure there is enough exposed wire to retrieve the chain for reinstallation.

Remove the spark plugs and install the upper camshaft journal holding device, tool No. 11-3-260/270/250. Tighten the hold down bolts in the spark plug bores to 17 ft. lbs. (23 Nm).

Apply a load to the bearing caps by rotating the eccentric shaft. This relieves the tension on the bearing cap bolts. Loosen and remove the bearing cap bolts.

Slowly and carefully rotate the eccentric of the cam cap holding fixture to release the camshaft.

Remove and rotate the camshaft fixture tool 180 degrees and repeat the above procedures to remove the other camshaft.

Remove the camshafts and the bearing caps. Note that the intake camshaft is marked E and the exhaust camshaft is marked A . The camshaft bearing are consecutively numbered and lettered with A or E to designate intake or exhaust side.

Hold the valve lash compensators in place using tool 11-3-250 and remove the bearing plate along with the valve plungers.

To install:

Apply fresh engine oil to the camshaft journals and lobes.

Place the camshaft in cam journals of the cylinder head.

Place the upper camshaft journal bearing caps on the camshaft in the correct order. Note that the intake camshaft is marked E and the exhaust camshaft is marked A . The camshaft bearing are consecutively numbered and lettered with A or E to designate intake or exhaust side.

With the spark plugs removed install the upper camshaft journal holding device, tool No. 11-3-260/270/250. Tighten the hold down bolts in the spark plug bores to 17 ft. lbs. (23 Nm).

Rotate the eccentric shaft of the camshaft journal holding fixture to seat the camshaft and journals into the cylinder head.

Use the holding fixture to secure the camshaft journals and camshaft into the cylinder head Install the camshaft journal bolts and torque as follows:

M6 fasteners: 89 inch lbs. (10 Nm)
M7 fasteners: 10 ft. lbs. (14 Nm)
M8 fasteners: 14 ft. lbs. (19 Nm)

Repeat the above procedures to install the second camshaft.

Remove the camshaft journal fixture tool.

Align the camshafts so that lobes of the intake and exhaust cams face each other for the No. 1 cylinder. The camshafts can be turned on the hexagon casting using a 1 ¹ / ₁₆ inch or 27mm open end wrench.
NOTE
Once the camshafts have been removed and reinstalled a waiting period dependent on the ambient temperature is necessary before rotating the engine. At room temperature wait 4 minutes to allow the lifters to compress fully. At temperatures down to 50°F (10°C) wait 11 minutes. At temperatures lower than 50°F (10°C) wait 30 minutes. This is to prevent contact between the valves and the piston tops. The engine may not be cranked under the same condition for a period of 10 minutes at room temperature; 30 minutes for temperatures down to 50°F (10°C); 75 minutes for temperatures below 50°F (10°C).

With the attached wire secured to the crankshaft cam chain, carefully raise the chain upward and apply a light tension to the chain, then while holding the chain, carefully rotate the engine clockwise to TDC on cylinder number one.

Lock the engine in the TDC position by placing the holding dowel tool No. 11-2-300 through the machined hole in the engine block, just inside of the transmission bell housing mounting tab located on the left lower portion of the engine block. Slide the locating dowel through the machined hole in the block and into the machined hole in the flywheel to prevent movement of the crankshaft.

Hold the camshafts TDC position by placing tool No. 11-3-240 on the valve cover mating surface at the back of the cylinder head and onto the squared ends of the camshafts, securing the camshafts such that 2 sides of the squared ends are parallel with the cam cover gasket mating surface. With the camshafts in this position, the arrows on the sprockets will be facing up.

Position the crankshaft cam chain over the exhaust cam chain sprocket and install the sprocket on the exhaust cam such that the slotted holes are centered with the fastener bores in the camshaft.

Install the hydraulic cam chain tensioner, and the cam chain guide, then the intake and exhaust camshaft sprockets along with the cam chain and remove the tool used to hold the hydraulic cam chain tensioner collapsed.

Install the crankshaft cam chain tensioner assembly, spring and cap nut.

Apply sealant to the upper corners of the cylinder head where the VANOS housing mounts and install a new VANOS housing gasket.

Press the helical gear of the VANOS assembly toward the housing and install the VANOS assembly. To do so on engines with a spring plate installed on the intake camshaft, place tool No. 11-5-490 onto the exhaust camshaft sprocket and carefully rotate the sprocket counterclockwise to allow the helical gear of the VANOS unit to thread into the intake camshaft and to allow the VANOS unit to be pulled into the front of the cylinder head.

If tool No. 11-5-490 is not available, move the camshaft sprockets to install the VANOS by using a suitable drift and soft faced mallet and lightly tapping on a sprocket tooth of the exhaust cam sprocket to rotate both cam sprockets counterclockwise, while alternately pressing on the VANOS unit to install it. This procedure may need to be repeated several times to fully install the VANOS unit, and must be performed very carefully, in such a manner to not distort or damage the teeth of the cam sprocket.
NOTE
Make sure when assembling the VANOS unit is able to rest on the front of the cylinder head without being forced or without binding. If the VANOS unit does not fully seat it may be necessary to reposition the camshaft sprockets such that the slots in the camshaft sprockets allow enough movement of the sprockets for the helical gear of the VANOS assembly to be fully seated during assembly.

Tighten the VANOS unit fastener and then torque the camshaft sprocket bolts of both the intake and exhaust cams to 16 ft. lbs. (22 Nm).

Remove the crankshaft TDC holding dowel tool No. 11-3-240 from the engine, and remove the camshaft TDC positioning tool No. 11-3-240 from the valve cover mating surface at the back of the cylinder head.

Slowly and carefully rotate the engine clockwise 4 complete revolutions bringing cylinder number 1 to TDC. If the engine binds for any reason stop immediately to evaluate and rectify the cause of the binding.

With cylinder number 1 at TDC slide the camshaft TDC positioning tool No. 11-3-240 over the ends of the cams and onto the valve cover mating surface. If the tool slides over the cams and is flush with the mating surface, the camshafts are properly timed. If the tool does not slide easily over the ends of the cams, or if the tool is not flush with the valve cover mating surface, the camshaft timing must be repeated until the tool fits squarely.

The balance of the assembly is in reverse order of disassembly.

Check all fluid levels as necessary.

Connect the negative battery cable.

M60/M62 Engines

Fig. Gap in increment gear must fit in special tool 11-3-440-M60/M62 engines

Fig. Left-side camshaft identification (cylinder bank 5 to 8): Hex-head (3) on intake camshaft between cylinder 7 and 8. Hex-head (4) on exhaust camshaft between cylinder 5 and 6-M60/M62 engines

Fig. Right-side camshaft identification (cylinder bank 1 to 4): Hex-head (2) on intake camshaft between cylinder 3 and 4. Hex-head (1) on exhaust camshaft between cylinder 1 and 2-M60/M62 engines

Fig. Camshaft positioning-M60/M62 engines

Fig. Install left-hand camshafts: Recesses in camshaft point downwards approximately 30-40 degrees from plane of cylinder head-M60/M62 engines

Fig. Install right-hand camshafts: Recesses in camshaft point upwards approximately 30-40 degrees from plane of cylinder head-M60/M62 engines

Left Camshaft (Cylinder Bank 5-8)

Disconnect negative battery cable.

Remove the left and right cylinder head covers.

Remove all spark plugs.

Remove the top left timing case cover.

Remove the splash guard.

Remove all oil lines to the left and right cylinder head.

Rotate the crankshaft in direction of rotation until the first cylinder is in TDC position.

Brace the camshaft on the hex head with a suitable open-end wrench and loosen the 3 accessible screws on each right sprocket approximately ¹ / ₂ a turn.
1. Turn the engine over once and loosen the remaining 3 screws on each right sprocket approximately ¹ / ₂ a turn.
2. Unscrew and remove the primary sprocket from the left-hand intake camshaft (cylinder bank 5-8). Secure the chain to prevent it from dropping.

Rotate the engine to 45 degrees BTDC setting position. Rotate the crankshaft against direction of rotation until the gap in the increment gear fits in the special tool 11-3-440 or equivalent.

Remove the screws on the exhaust camshafts with a spanner tool or equivalent.

Remove the screws on the exhaust camshaft sprocket. Do not remove the sprocket.

Compress the chain tensioner and install special tool 11-3-420 or equivalent to lock the tensioner in place.

Lift off both secondary camshaft sprockets together with the chain.

Rotate the intake and exhaust camshafts to the installed position:
1. Using special tool 11-3-430 or equivalent, rotate the camshafts until the recess in both camshaft flange points approximately 30-40 degrees downwards from the plane of the cylinder head.
2. Check the installed position by installing special tool 11-2-430 or equivalent to the camshafts. The cylinder designation of the special tool must point upwards.

Loosen the both camshaft bearing caps uniformly from outside to inside ¹ /₂ turn.

Remove all bearing caps. Label each bearing cap to facilitate re-assemble and position aside.

Remove the camshafts noting their locations.

To remove the hydraulic valve lifters use special tool 11-3-250 to pull them out of the cylinder head. Make sure that no damage occurs to the guides in the head. Inspect the bearing surfaces of the bucket tappets (lifters) for wear and scoring.

To install:

If the lifters were removed, install them with special tool 11-32-250 or equivalent.

Lubricate and install the camshafts in their correct position.
NOTE
The intake camshaft will have a hexagon between cylinders 7 and 8. The exhaust camshaft will have the hexagon between cylinders 5 and 6.

Rotate the intake and exhaust camshafts to the installed position:
1. Using special tool 11-3-430 or equivalent, rotate the camshafts until the recess in both camshaft flange points approximately 30-40 degrees downwards from the plane of the cylinder head.
2. Check the installed position by installing special tool 11-2-430 or equivalent to the camshafts. The cylinder designation of the special tool must point upwards.

Install the bearing caps. Tighten the bearing caps from outside to inside in 1/2 turn increments. Torque the bolts to 9-13 ft. lbs. (12-17 Nm).
NOTE
Do not confuse camshaft bearing caps of cylinders No. 1-4 and 5-8. The exhaust camshaft bearing caps are marked with A1-A5 from intake side. The intake camshaft bearing caps are marked with E1-E5 from intake end.

Fit the special tool 11-3-430 or equivalent to the camshaft. Rotate the camshaft until the marker bores face upwards.
1. Install special tools 11-2-442/446 or equivalent to the camshaft on cylinder bank 5-8.
2. Install special tools 11-2-441/445 or equivalent to the camshaft on cylinder bank 1-4.
3. Using a suitable open-end wrench, align all camshafts in such a way that the special tools fit on the cylinder heads without any gaps.
4. Fit special tools 11-2-443 or equivalent to special tools 11-2-441/442/445/446 and secure them with special tools 11-2-444 using spark plug threads.

Install the secondary sprockets together with chain to the camshafts on cylinder bank 5-8.

Install the screws on the exhaust camshaft sprocket and tighten snug.

Remove the special tool used to lock the chain tensioner in position.

Rotate the engine from 45 degrees BTDC in direction of rotation as far as TDC setting. Install special tool 11-2-300 at the flywheel to lock the crankshaft in TDC position.

Assemble the primary sprocket and chain to the intake camshaft with the arrow pointing upwards (in cylinder axis) and the long bores centrally aligned. Install the screws snug.

Install the special tool 11-3-390 or equivalent in the right timing case cover and with a suitable torque wrench, tension the tool to 1.3 Nm.

Tighten the sprockets to 11 ft. lbs (15 Nm) in the following order:

All screws on the left exhaust camshaft
3 screws in the right exhaust camshaft
All screws on the left intake camshaft
3 screws in the right intake camshaft

Remove special tools 11-2-444/443/441/445.

Remove special tools 11-2-444/443/442/446.

Remove special tool 11-2-300 used to locked the crankshaft in TDC position.

Turn the engine over once.

Tighten the remaining 3 screws on right exhaust camshaft and remaining 3 screws on right intake camshaft to 11 ft. lbs. (15 Nm).

Relieve the load and remove the special tool 11-3-390 or equivalent from the right timing case cover.

The balance of installation is the reverse of the removal procedure.

Start the engine. Check for leaks and proper operation.

Right Camshaft (Cylinder Bank 1-4)

Disconnect negative battery cable.

Remove the left and right cylinder head covers.

Remove all spark plugs.

Remove the fan assembly.

Remove the top right timing case cover.

Remove the splash guard.

Remove all oil lines to the left and right cylinder head.

Rotate the crankshaft in direction of rotation until the first cylinder is in TDC position.

Brace the camshaft on the hex head with a suitable open-end wrench and loosen the 3 accessible screws on each left sprocket approximately ¹ / ₂ a turn.
1. Turn the engine over once and loosen the remaining 3 screws on each left sprocket approximately ¹ / ₂ a turn.
2. Unscrew and remove the primary sprocket from the right-hand intake camshaft (cylinder bank 1-4). Secure the chain to prevent it from dropping.

Rotate the engine to 45 degrees BTDC setting position. Rotate the crankshaft against direction of rotation until the gap in the increment gear fits in the special tool 11-3-440 or equivalent.

Remove the screws on the exhaust camshaft sprocket. Do not remove the sprocket.

Compress the chain tensioner and install special tool 11-3-420 or equivalent to lock the tensioner in place.

Lift off both secondary camshaft sprockets together with the chain.

Rotate the intake and exhaust camshafts to the installed position:
1. Using special tool 11-3-430 or equivalent, rotate the camshafts until the recess in both camshaft flange points approximately 30-40 degrees upwards from the plane of the cylinder head.
2. Check the installed position by installing special tool 11-2-430 or equivalent to the camshafts. The cylinder designation of the special tool must point upwards.

Loosen the both camshaft bearing caps uniformly from outside to inside ¹ /₂ turn.

Remove all bearing caps. Label each bearing cap to facilitate re-assemble and position aside.

Remove the camshafts noting their locations.

To remove the hydraulic valve lifters use special tool 11-3-250 to pull them out of the cylinder head. Make sure that no damage occurs to the guides in the head. Inspect the bearing surfaces of the bucket tappets (lifters) for wear and scoring.

To install:

If the lifters were removed, lubricate and install them with special tool 11-32-250 or equivalent.

Lubricate and install the camshafts in their correct position.
NOTE
The intake camshaft will have a hexagon between cylinders 3 and 4. The exhaust camshaft will have the hexagon between cylinders 1 and 2.

Rotate the intake and exhaust camshafts to the installed position:
1. Using special tool 11-3-430 or equivalent, rotate the camshafts until the recess in both camshaft flange points approximately 30-40 degrees upwards from the plane of the cylinder head.
2. Check the installed position by installing special tool 11-2-430 or equivalent to the camshafts. The cylinder designation of the special tool must point upwards.

Install the bearing caps. Tighten the bearing caps from outside to inside in 1/2 turn increments. Torque the bolts to 9-13 ft. lbs. (12-17 Nm).
NOTE
Do not confuse camshaft bearing caps of cylinders No. 1-4 and 5-8. The exhaust camshaft bearing caps are marked with A1-A5 from intake side. The intake camshaft bearing caps are marked with E1-E5 from intake end.

Fit the special tool 11-3-430 or equivalent to the camshaft. Rotate the camshaft until the marker bores face upwards.
1. Install special tools 11-2-442/446 or equivalent to the camshaft on cylinder bank 5-8.
2. Install special tools 11-2-441/445 or equivalent to the camshaft on cylinder bank 1-4.
3. Using a suitable open-end wrench, align all camshafts in such a way that the special tools fit on the cylinder heads without any gaps.
4. Fit special tools 11-2-443 or equivalent to special tools 11-2-441/442/445/446 and secure them with special tools 11-2-444 using spark plug threads.

Install the secondary sprockets together with chain to the camshafts on cylinder bank 1-4.

Install the screws on the exhaust camshaft sprocket and tighten snug.

Remove the special tool used to lock the chain tensioner in position.

Rotate the engine from 45 degrees BTDC in direction of rotation as far as TDC setting. Install special tool 11-2-300 at the flywheel to lock the crankshaft in TDC position.

Assemble the primary sprocket/chain with sensor pin to the intake camshaft with the arrow pointing upwards (in cylinder axis) and the long bores centrally aligned. Install the screws snug.

Install the special tool 11-2-400 or equivalent to the right cylinder head (cylinder bank 1-4). Install the special tool 11-3-390 to special tool 11-2-400. Using a suitable torque wrench, tension the tool to 1.3 Nm.

Tighten the sprockets to 11 ft. lbs (15 Nm) in the following order:

3 screws on the left exhaust camshaft
All screws on the right exhaust camshaft
3 screws on the left intake camshaft
All screws in the right intake camshaft