Experimental Study on Camshaft Failure in Sedan Cars

A camshaft is a shaft with a protrusion or cam located in the cylinder head to open and close the ignition engine valve, drive the distributor shaft, and serve as a mechanical fuel pump. Therefore, this study was conducted to analyze the causes of the camshaft failure in a sedan car. The failure was in the form of a fracture between the intake valves of the second cylinder even though the car was relatively new with a lifespan of 15 months. This was achieved through the assessment of the chemical composition, hardness, and microstructure as well as the observation of the fracture surface using SEM. The results of the chemical composition test classified the camshaft as gray cast iron ASTM A48 Grade 40 which was considered not suitable and led to the fracture. Moreover, porosity was also found in the camshaft and this showed it was not strong enough to receive stress.