Relieving the chain tensioner at cylinder bank 1 for checking or setting the valve timings
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.
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.
- Make sure that the chain drive is loaded at the same time on the central bolt of the engine and on the VANOS central valve on the exhaust.
The movement of the chain tensioner piston must be observed in this process.
To do this, the following steps must be carried out at the same time:
- Keep the VANOS central valve on the exhaust under tension in clockwise direction with a support person.
The VANOS central valve on the exhaust must not be twisted.
- Turn engine counter clockwise at central bolt (1).
Slackening the hydraulic chain tensioner of cylinder bank 1
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.
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.
- Position the special tool 0 491 012 (11 4 120) (3) in the bore and fasten the chain tensioner piston.
- Make sure that the chain drive is relieved at the same time on the central bolt of the engine and on the VANOS central valve on the exhaust. To do this, carry out the following steps at the same time:
- Relieve the chain drive clockwise at the central bolt.
- Relieve the chain drive counterclockwise at the VANOS central valve on the exhaust.