The auxiliary engine is a vital component on ships, including the MV Pancaran I 5505, as it serves as the power source for all primary and supporting equipment on board. Due to its high workload, the auxiliary engine requires regular maintenance to maintain optimal performance. One of the most important maintenance tasks is a general overhaul (GO).

This article discusses in full the process, objectives, and benefits of General Overhaul Auxiliary Engine on the MV Pancaran I 5505 ship as part of preventive maintenance in the shipping industry.

General overhaul of auxiliary engine includes the following important stages:

Disassembly of Main Components

• Remove the cylinder head, connecting rod, and piston assembly.
• Dismantle the exhaust valve, intake valve, and rocker arm.
• Remove the fuel injection pump and injectors for inspection.
• Remove the lube oil pump and water pump for internal inspection.

Measurement & Inspection

• Checking cylinder liner wear using a cylinder gauge.
• Measuring piston ring gap, piston skirt, and axial clearance.
• Inspecting main bearings and crankpin bearings to detect scoring or overheating.
• Calibrating fuel injectors and fuel pumps.
• Compression pressure testing after temporary assembly.

Cleaning and Reconditioning

• Cleaning carbon deposits on the cylinder head and piston crown.
• Lapping valve seats for optimal sealing.
• Flushing the lub oil system to ensure there is no sludge.
• Cleaning the seawater cooler and lub oil cooler using chemical descaling.

Component Replacement

Some parts that are replaced with original spare parts:

• Piston ring set
• Exhaust and intake valves
• Main bearings and connecting rod bearings
• Gasket and rubber seal set
• Fuel injection nozzles
• Lubricating oil and fuel filters

Assembly & Testing (Commissioning)

• Engine running tests at varying loads of 25%, 50%, 75%, and 100%.
• Exhaust gas temperature measurements for each cylinder.
• Vibrations and leak checks throughout the system.
• Evaluation of fuel consumption performance after overhaul.

Findings During Overhaul

During the work process, several critical findings were identified:

Excessive Piston Ring Wear

Increased gas blow-by occurs, resulting in decreased compression pressure.

Cylinder Liner Scoring

Fine lines are found due to lack of lubrication during certain operating hours.

Burned Exhaust Valve

The exhaust valve is deformed and has erosion on the seating surface.

Carbon Deposits Accumulate

Carbon buildup on the piston crown and exhaust passage causes the exhaust temperature to be unstable.

Final Results After Overhaul

After the general overhaul was completed, significant results were obtained:

• Compression pressure across all cylinders returned to factory standards.
• Inter-cylinder exhaust temperatures became more stable, with deviations of <10°C.
• Engine oil consumption decreased by 25%.
• Combustion performance was optimized after injector calibration.
• The engine ran smoother with lower vibration.
• The AE was ready to operate again with high reliability, both during vessel maneuvering and under heavy electrical loads.

Conclusion

The general overhaul of the MV Pancaran I 5505’s auxiliary engine was a strategic step to maintain the performance and reliability of the vessel’s electrical system. With in-depth inspections, appropriate parts replacement, and accurate commissioning, the AE was able to return to operating condition.

This case study demonstrates that regular maintenance is a critical investment to prevent major damage, optimize operating costs, and enhance navigational safety.