09-11-2012, 11:09 AM
Basic Parts of the S.I Engine
Engine piston description.pptx (Size: 875.05 KB / Downloads: 44)
Piston Pins
Also known as the wrist pin, it connects the piston to the small end of the connecting rod.
It transfers the force and allows the rod to swing back and forth.
Crankshaft
Along the the piston pin and connecting rod it converts the up and down motion (reciprocating) of the engine to spinning (rotary) motion.
Cylinder Head
Forms the top of the combustion chamber.
Contains the valves, the passageways for the fuel mixture to move in and out of the engine.
Camshaft
Through the use of an eccentric the cam lobes push the valves open.
The valve springs close them.
Spark Plug
Electric match used to begin the combustion process of burning air and gasoline to create heat.
Engine Related Terms
TDC (top dead center)
BDC (bottom dead center)
Stroke
Bore
Revolution
Compression Ratio
Displacement
Cycle
Intake Stroke
Intake valve opens.
Piston moves down, ½ turn of crankshaft.
A vacuum is created in the cylinder.
Atmospheric pressure pushes the air/fuel mixture into the cylinder.
Compression Stroke
Valves close.
Piston moves up, ½ turn of crankshaft.
Air/fuel mixture is compressed.
Fuel starts to vaporize and heat begins to build.
The Cycle
How many revolutions of the crankshaft does it take to complete the four strokes?
If an engine idles at 500 rpm, how many power strokes occur per minute?
How many power strokes per second