Checking the balance shaft base position of the 628 series engine
1 - Intake camshaft gear; 2 - Exhaust camshaft gear; 3 - Lid; 3a - Bottom bolt; 3b - Upper bolt; 5 - Spring; 7 - Balance shaft sprocket; 9 - Installation marks
Checking the balance shaft base position of the 628 series engine
5 - Spring; 6 - Marking; 7 - Balance shaft sprocket
1. Illustrative material for checking the basic position of the balance shaft on 628 series engines is presented in the illustrations to which all references in the text refer.
2. Remove the cylinder head covers.
3. Remove the electric cooling fan assembly (see Chapter Cooling, heating and air conditioning systems).
4. Unscrew the lower bolt (3a) of the cover (3), - in order to provide access to the bolt, turn the crankshaft in the normal direction.
5. Bring the piston of the first cylinder to the TDC position.
6. Unscrew the upper bolt (3b) and remove the cover (3).
7. Remove the centrifuge.
8. Make sure that the tensioner (9) provides the required tension force of the timing chain.
9. Install the cover (3) on the crankcase and secure it with the upper bolt (3b).
10. Turn the crankshaft two full turns in the normal direction, again bringing the piston of the first cylinder to the TDC position.
11. Remove the cover (3) again.
12. Make sure that the basic installation of the camshafts is correct (see Section Setting the base position of the camshafts).
Original published on the website [MERCEDESMAN.ru]
13. Check the correct basic installation of the balance shaft, the spring (5) of which should occupy the position shown in the picture, and the marking (6) on the sprocket (7) should be slightly offset from the "12 o'clock" position.
14. Proceeding in the reverse order of dismantling, install the removed components back into place.