Automotive piston design

2. Aim: what are parts of a piston?

4. Aluminum piston for light weight and strength. Piston Construction Skirt - below pin hole. Connecting rod to crankshaft. Rapid changes of speed and direction. Pin connects piston to connecting rod. Next > Compression height Skirt Cylinder Connecting rod Pin hole

5. 1 A) The side B) The compression height C) The skirt D) The connecting Rod What is the part of the piston below the pin called? Question

6. Top of piston is hottest. Piston Shape Piston tapers to top. Cam-ground piston, oval for expansion. Expands across minor diameter. Next > 300-350ºF 300-450ºF 600-700ºF Minor diameter

7. 2 The top of a piston will be slightly oval in shape when cold. Is this true or false? Answer T rue or F alse. Question

8. Piston Rings Compression rings prevent pressure leakage. Two compression rings. One oil ring. Ring gap to allow expansion. Expand when hot. Next > Angle joint Step joint Butt joint

9. Oil Ring Wipes oil off cylinder wall. Holes in piston under oil ring. Returns oil to crankcase. Piston pin hole below oil ring. Next >

10. Connecting Rod Construction Connecting rod has a small end and a big end. Big end has bearing inserts. Small end may have a bushing for the piston pin. There may be an oil hole in the small end. Each rod and cap must be numbered for identification. Next >

12. 4 A) Bushing B) Snap ring C) Connecting rod D) Piston ring What connects the piston to the crankshaft? Question

15. 6 A) Oil B) Water C) Piston pins D) Counterweights Which of the following are added to reduce vibration in a crankshaft? Question

16. 7 A) Crankpin B) Counterpin C) Oil pressure D) Counterweight What is another name for the journal of a crankshaft? Question

17. Oil Holes and Grooves The crankshaft rotates in the bearing shells between the cylinder block and the caps. Grooves and holes are included to allow oil circulation. Next > Cylinder block Bearing cap

18. 8 A) To allow air to circulate B) To allow for expansion C) To help relieve stress D) To allow oil to circulate Bearings have holes and grooves in them. Why is this? Question

20. Thrust Bearings and Washers Prevents lateral movement of the crankshaft. May be thrust flanges on main bearings, or separate washers. Main bearing and connecting rod (big end) bearing shown. Next > Bearing cap Crankshaft Bearing Thrust washer Main bearing

21. Seal keeps the oil in, and dust and dirt out. Oil Seals Recess in cap locates neoprene seals. Next > Main bearing seal Oil groove Oil seal recess Body Inner seal lip Spring Outer seal lip

22. 9 Main bearing oil seals are usually made of silicone. Is this true or false? Answer T rue or F alse. Question

23. Shafts are chain or belt driven from crankshaft. Balancer Shafts Reduce vibration forces and therefore engine noise. Oil pressure is fed to bearings. Next > Guide Drive chain Balancer shafts Bearing housing

24. 10 A) To prevent the engine from running too fast B) To keep the piston moving when the engine cuts out C) To enable better starting and stopping D) To reduce vibration and noise What is the purpose of Balancer Shafts? Question