Engine Rockerarm

Introduction

In a four stroke internal combustion (IC) engine, lifting of the cam lobe causes the rocker arm to push down upon the valve stem. This movement opens the associated valve; valve springs return the valve back to the closed position.

 

Additional Resources

https://en.wikipedia.org/wiki/Rocker_arm

https://www.britannica.com/technology/emission-control-system

http://performancetrends.com/Definitions/Rocker-Arms.htm