Vibration Analysis of a Diesel Engine at Cranking and Idling Modes and Its Mounting System

This paper presents the procedure to evaluate the force oscillations, caused by the idling and cranking of a diesel engine, from measuring three directional forces at the mounting points of the engine for front-wheel-drive-vehicles. It is recognized that the same values for the force oscillations were obtained for a given engine under a constant engine speed at idling, irrespective of the condition of the engine supporting. Moreover, the optimum mounting configuration for idling and cranking was quantitatively investigated through computer simulation of the vibration model which regarded the force oscillation as the excitation force in the equations of motion.