THE BEECHMONT CREST AUTOMOTIVE LEARNING ZONE

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Piston

A complex, machined metal engine component. The piston transfers the power from the combustion of fuel to the connecting rod and the crankshaft. 

The piston consists of the following elements:

 

• Piston head: The top portion of the piston. The piston head must be thick and durable because it comes into direct contact with the heat and pressure of the combustion process in the combustion chamber.
• Piston oil holes: Holes through which oil passes. The oil flows onto the cylinder wall, and then drains into the crankcase.
• Piston ring grooves: Machined grooves where the piston rings fit.
• Piston rings: A set of rings that seal the space between the outside surface of the piston and the cylinder wall (piston clearance). The rings keep combustion pressure out of the crankcase and oil out of the combustion chambers.
• Piston pin: A pin that fits through a hole in the piston and a hole in the connecting rod. The piston pin enables the swinging movement of the piston on the connecting rod.