11 31 090 Installing and removing/replacing chain tensioner piston (N54, N54T)
Necessary preliminary tasks
Remove COOLANT EXPANSION TANK (E89 only)
Release chain tensioner (1).
Tightening torque: 11 31 5AZ .
IMPORTANT:
Have a cleaning cloth ready. A small quantity of engine oil will emerge after the screw connection has been released.
Make sure no oil runs onto the belt drive.
Installation note:
No sealing ring is fitted during series-production assembly.
A sealing ring must be fitted by service personnel when the chain tensioner is fitted.
If the chain tensioner is reused, its oil chamber must be drained. Place chain tensioner on a level working surface and slowly compress.
Repeat procedure twice.
Assemble engine.