Chapter 11 PowerPoint

Define these Technical Terms using the textbook:

1. camshaft

2. combustion chamber

3. connecting rod

4. crankshaft

5. cylinder head

6. engine block

7. intake manifold

8. piston

9. valve cover

Answer these discussion questions using the textbook:

1. List the 4 strokes of the 4-stroke (4-cycle) engine.

Read the chapter summary below:

■ The engine is the source of power for the vehicle. For this reason, it is also called a powerplant.

■ When the piston is at its highest point in the cylinder, it is at TDC (top dead center). When the piston slides to its lowest point in the cylinder, it is at BDC (bottom dead center).

■ The term engine bottom end generally refers to the block, crankshaft, connecting rods, pistons, and related components.

■ The crankshaft harnesses the tremendous force produced by the downward thrust of the pistons.

■ The engine main bearings are removable inserts that fit between the block main bore and crankshaft main journals.

■ Main bearing clearance is the space between the crankshaft main journal and the main bearing insert.

■ Crankshaft oil seals keep oil from leaking out the front and rear of the engine.

■ The connecting rod fastens the piston to the crankshaft. It transfers piston movement to the crankshaft rod journals.

■ The engine piston transfers the pressure of combustion (expanding gas) to the connecting rod and crankshaft.

■ Piston clearance is the amount of space between the sides of the piston and the cylinder wall.

■ The piston rings seal the clearance between the outside of the piston and the cylinder wall.

■ The compression rings prevent blowby (combustion pressure leaking into engine crankcase).

■ The main job of oil rings is to prevent engine oil from entering the combustion chamber.

■ The term engine top end generally refers to the cylinder heads, valves, camshaft, and related components.

■ The camshaft has lobes that open the valves.

■ A valve lifter usually rides on the cam lobes and transfers motion to the rest of the valvetrain.

■ Engine valves open and close the ports in the cylinder head.

■ The valve spring assembly is used to close the valve.

■ The engine front end operates the engine camshaft and, sometimes, the oil pump, water pump, engine sensors, and diesel injection pump.

■ A crank damper is a heavy wheel on the crankshaft snout. It is mounted in rubber and helps prevent crankshaft vibration and damage.