Slackening the chain tensioner of cylinder bank 2

NOTE: RISK OF DAMAGE
Damage to timing chain or timing chain drive.
Turning the engine without chain tensioner or special tool can result in damage to the timing chain and timing chain drive.

Always turn the engine with the chain tensioner or the special tool.

NOTE: TECHNICAL INFORMATION
Conduct the following operation with the assistance of a second person.

Make sure the chain drive is simultaneously loaded on the central bolt of the engine and on the VANOS exhaust central valve.
Observe the movement of the chain tensioner piston.

Perform the following steps simultaneously:
With a second person, keep the VANOS exhaust central valve under tension clockwise.
The VANOS exhaust central valve must not be twisted.

Courtesy of BMW OF NORTH AMERICA, INC.
Turn engine counter clockwise at central bolt (1) .

Courtesy of BMW OF NORTH AMERICA, INC.

Slackening the hydraulic chain tensioner of cylinder bank 2

NOTE: RISK OF DAMAGE
Damage to timing chain or timing chain drive.
Turning the engine without chain tensioner or special tool can result in damage to the timing chain and timing chain drive.

Always turn the engine with the chain tensioner or the special tool.

Courtesy of BMW OF NORTH AMERICA, INC.

Position the special tool 0 491 012 (11 4 120) (3) in the bore and fasten the chain tensioner piston.

Make sure the chain drive is simultaneously relieved on the central bolt of the engine and on the VANOS exhaust central valve.
Perform the following steps simultaneously:
Relieve the chain drive clockwise at the central bolt.

Courtesy of BMW OF NORTH AMERICA, INC.
Relieve the chain drive counterclockwise at the VANOS exhaust central valve.

Courtesy of BMW OF NORTH AMERICA, INC.