Evaluation of the degree of stretching of the timing chain of the M628 engine
1. The degree of stretching of the timing chain can be determined indirectly by the position of the pulley (2) of the accessory drive belt on the intake camshaft (1).
2. Remove the right cylinder head cover (see illustrations Installation details of cylinder head covers for the M682 engine (1 of 2) and Installation details of cylinder head covers for the M682 engine (2 of 2)).
3. Remove the accessory drive belt (see Section Replacement of the auxiliary drive belt and elements of its tensioning mechanism).
4. Turn the engine in the normal direction (arrow) so that the intake camshaft (1) can be locked by the rod (4) - thread the rod.
5. If the pulley (2) of the accessory drive belt with the shaft (1) locked is displaced by more than 11° after TDC relative to the installation mark (3) (see scale on pulley), the timing chain should be replaced.
6. Installation is carried out in reverse order.