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.