Figure 2.74. Oil circulation in the engine cylinder block:
1. Cover of the camshaft chain drive,
2. Chain tensioner,
3. Oil pressure sensor,
4. Check valve,
5. Sealing ring,
6. Crankshaft,
7. Main oil line,
8. Lubrication of the piston pin,
9. Ball plug,
10. Crankshaft main bearing,
11. Connecting rod bearings,
12. Oil filter,
13. Oil pump,
14. Pressure reducing valve,
15. Oil radiator.
A. Oil supply from the oil pump,
B. Oil supply to the oil radiator,
C. Oil supply from the oil radiator,
D. Oil supply to the main line,
E. Oil supply to the cylinder head,
F. Oil supply to the chain drive tensioner.
Figure 2.75. Oil circulation in the camshaft chain drive cover:
Oil drain line:
16. Adapter,
17. Cone valve,
18, 20. Plug with gland,
19. Spring.
Oil supply to the oil filter:
21. Bypass valve,
22. Gasket,
23. Sealing ring,
24. Oil filter cover,
25. Filter element retainer,
26. Filter element,
27. Oil pump housing,
28. Oil filter filling valve.
Oil supply to the oil radiator:
29. Plug with gland,
30. Spring,
31. Cone valve.
A. Oil supply from the oil pump,
B. Oil supply to the oil radiator,
C. Oil supply from the oil radiator,
D. Oil supply to the main line.
Figure 2.76. Oil circulation in the cylinder head:
32. Ball plug,
33. Covers of oil channels in camshafts,
34. Hydraulic compensators,
35. Exhaust camshaft,
36. Oil supply to hydraulic compensators of exhaust valves,
37. Intake camshaft,
38. Oil supply to the hydraulic compensators of the intake valves,
39. Seal,
40. Cork.
E. Oil supply to the cylinder head.
Figure 2.77. Lubrication system drain line (diagram):
41. Drain line from cylinder head/cylinder block,
42. Cork (glued),
43. Common drain line (cylinder block),
44. Tube for draining oil into the pan.
[Original source of information: mercedesman]