1Mechanical Engineering Department, Faculty of Engineering, University of Muhammadiyah Jakarta, Jakarta, 10510, Indonesia
2Automotive and Heavy Equipment Department, Faculty of Engineering, University of Muhammadiyah Jakarta, Jakarta, 10510, Indonesia
*Corresponding author e-mail: anwar.ilmar@ftumj.ac.id
Online published on 27 April, 2016.
Damage to the outboard motor FT50CEHD occurs when the boat was used for 10 hours. Damage includes to the outbreak of cylinder block, curved connecting rod which caused fracture of the bolt connecting rod, and its occurs just in cylinder number one. The purpose of this research is to determine the main cause of damage to the connecting rod bolts FT50CEHD outboard motor. The method used was a visual inspection/non-destructive test, chemical analysis, Mechanical Properties Analysis and Metallography Examination by SEM (Scanning Electron Microscope) on the bolt fracture surface. Results of laboratory testing bolt material in good condition in terms of chemical composition and mechanical properties as in accordance with the standard material. Typography broken bolt shows the type of ductile fracture and the fracture surface showed dimple fracture in the middle and on the edge was the shear fracture. This type of fracture was caused due to the excessive tensile and torsional force. Conclusion of this research was the connecting rod bolt damage occurred because of excessive tightening torque.
Outboard engine, connecting rod bolts, scanning electron microscope, mechanical properties
