Main Engine Overhaul
(MAN B&W 6S60MC-C)
Our team completed a thorough overhaul of the MAN B&W 6S60MC-C main engine, restoring its efficiency and reliability. The process started with a detailed assessment, identifying critical areas for maintenance. Key components such as the crankshaft, bearings, cylinder heads, and pistons underwent inspections, repairs, and necessary replacements. Fuel injectors and pumps were calibrated to enhance combustion efficiency and reduce emissions. The exhaust system was fully reconditioned to maintain optimal airflow and structural integrity. The overhaul ensured smooth operation under demanding conditions, extending the engine’s lifespan while reducing downtime and maintenance costs.
Cylinder Cover & Liners Overhaul
- Removed, dismantled, and cleaned all six cylinder covers.
- Transported covers to the workshop for complete disassembly.
- Removed all attached components, including valves and indicator cocks.
- Chemically cleaned covers and unclogged cooling holes.
- Performed dye penetration tests on combustion areas.
- Replaced worn-out O-rings and gaskets.
- Conducted pressure testing to ensure proper sealing.
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Reassembled and refitted the covers onboard.
Servicing the cylinder covers and their components was essential to restore safe and efficient engine operation. All six covers were cleaned, cooling passages unclogged, and key parts—including exhaust valves, starting air valves, safety valves, and injectors—were overhauled, calibrated, and tested. Additionally, the cylinder liners were withdrawn, cooling surfaces cleaned, lube oil quills dismantled, permeability restored, and new O-rings fitted before refitting, securing thermal efficiency and oil flow integrity. These works ensured proper combustion, cooling, and sealing, preventing future mechanical failures.
Cylinder Liner On-Site Honing
INJEGOV SA performed on-site cylinder liner honing using a Chris-Marine precision honing machine, a process essential for restoring proper surface finish in low-speed engines. The honing procedure included an initial pass with a medium diamond stone to reduce roughness to 2 μm, followed by a fine ceramic stone to achieve a final Ra of 1–1.5 μm, ensuring optimal oil retention and piston ring seating. Conducted directly onboard, this method eliminates the need for liner removal and reduces downtime, while maintaining OEM surface specifications. Final liner diameters were measured and recorded after completion to confirm machining accuracy.
Cylinder Cover Reconditioning
Piston Overhaul
Removed and dismantled six pistons for thorough inspection.
- Cleaned, calibrated, and replaced worn piston rings
- Installed new piston crowns supplied by the owner
- Conducted dye penetration tests to check for cracks or structural weaknesses.
- Reassembled and refitted pistons with precision alignment.
Overhauling of the pistons and stuffing boxes was vital to restore compression efficiency and prevent oil contamination. All six pistons were dismantled, cleaned, calibrated, and tested, with liners also serviced accordingly. Piston crowns were replaced with new Owner-supplied units, and skirts, rods, and o-rings were overhauled. Stuffing boxes were also cleaned, calibrated, and partially renewed, with full replacements carried out on some units.
Piston Crown Reconditioning
Piston crowns underwent complete reconditioning, beginning with dimensional checks and cleaning by sandblasting. Grooves and diameters were rebuilt using SAW welding, followed by annealing at 750°C in a digitally controlled oven. The crowns were then CNC-machined to OEM specifications, hard chrome plated at the grooves, and hardness-tested. Final grinding and super-finishing ensured full dimensional accuracy and performance readiness.
ME _ MAN B&W 6S60MC-C _ Piston Crown Reconditioning
ME _ MAN B&W 6S60MC-C _ Piston Rod Repairs (2)
ME _ MAN B&W 6S60MC-C _ Piston Rod Repairs
ME _ MAN B&W 6S60MC-C _ Shock Absorber Piston Reconditioning
ME _ MAN B&W 6S60MC-C _ Exhaust Valve Spindle & Seat (2)
ME _ MAN B&W 6S60MC-C _ Exhaust Valve Spindle & Seat (3)
ME _ MAN B&W 6S60MC-C _ Exhaust Valve Spindle & Seat (4)
ME _ MAN B&W 6S60MC-C _ Exhaust Valve Spindle & Seat
ME _ MAN B&W 6S60MC-C _ Piston Crown Reconditioning (2)
ME _ MAN B&W 6S60MC-C _ Piston Crown Reconditioning (3)
Fuel Pumps Overhaul
- Removed and dismantled six high-pressure fuel oil pumps.
- Transported pumps to the workshop for complete overhauling.
- Inspected and calibrated pump barrels and plungers.
- Checked suction and delivery valves for wear, replacing components as needed.
- Conducted pressure tests to verify proper fuel injection timing.
- Reassembled and refitted the fuel pumps onboard.
The overhaul of the main engine fuel pumps was crucial for restoring precise fuel delivery and combustion timing. All six high-pressure pumps were dismantled, cleaned, calibrated, and reassembled with new Owner-supplied barrel and plunger sets. Worn suction and puncture valves were also replaced, and each pump was set according to the fuel timing table provided. Additionally, the shock absorbers were overhauled in the workshop, with renewal of all o-rings and seal rings to ensure proper sealing and smooth operation.
Fuel Pump Reconditioning
Fuel pump casings were reconditioned by pre-machining the upper and lower internal diameters, followed by fabrication of two custom cast iron bushes. The bushes were shrink-fitted into place and secured with safety pins. Final machining was performed to bring the internal diameters, in way of the new bushes, back to standard dimensions, restoring proper fit and function.
Read the full Auxiliary Engine Overhaul case study for a complete view of the project
This main engine overhaul was part of a broader service project. We also carried out a full MAN B&W 6L23/30H auxiliary engine overhaul, covering cylinder head and liner reconditioning, on-site honing, and fuel system calibration.
