Abstract:
The Turbocharger is a vital component of a ship’s main engine that utilizes exhaust gas
energy to drive the turbine and compressor, thereby increasing the air supply to the
combustion chamber and improving engine power output. This research was motivated
by a surging incident on the main engine Turbocharger of MV. CMA CGM HOMERE on
11 May 2025 during the voyage from Kingston, Jamaica to Rio Haina, Dominican
Republic, which forced the engine speed to be reduced from 73 rpm to 55 rpm, as well as
a drop in scavenging air pressure from 1.05 bar to 0.45 bar accompanied by an increase
in cylinder inlet air temperature on 19 May 2025.
The research problems addressed are why the Turbocharger speed became abnormal and
why the main engine performance decreased due to scavenging air entering the
combustion chamber in an unclean condition. This study employed a descriptive
qualitative method with a case study and problem-solving approach, using data collection
techniques including direct observation, interviews with the Second Engineer and the
Chief Engineer, and documentation studies during the author’s sea practice on board.
The results show that the abnormal Turbocharger speed was caused by a nozzle ring
blocked by carbon deposits and soot, as well as a roller bearing whose clearance
exceeded the normal limit (axial 0.19 mm and radial 1.2 mm against the normal limits of
0.16 mm and 0.99 mm). The decrease in scavenging air pressure was caused by a dirty
air filter (coper mesh) and an unmaintained intercooler. The problems were solved by
cleaning the nozzle ring using hot water pressure injection while the engine was running
at slow ahead, replacing the roller bearing with a new one according to manufacturer
specifications, cleaning the air filter regularly every three months, and performing
intercooler maintenance through circulation and injection systems.
This study recommends that shipping companies ensure the availability of critical
Turbocharger spare parts on board, that marine engineers improve supervision and
thoroughness in routine inspections, and that the crew consistently implement the
Planned Maintenance System (PMS) to prevent similar disturbances in the future
