2. Plain bearings

3. Main bearings

4. Main rod cam

5. Crankshaft

6. Rocker arms

7. Lifters

8. Splash Lubrication

9. Spray Lubrication

10. Roller and ball bearings

11. Gear reduction systems

12. Splash and/or Spray

13. Cylinder walls

14. Piston

15. Valves

16. Lubrication

17. Wet Sump

18. Oil is stored within the engine

19. Dry Sump

20. Oil is stored external to the engine in an oil tankScavenge Pump: 300 times greater capacity than pressure pumps. Return oil takes up more space because 1. It’s hot and 2. It’s been aerated. Ashless dispersing