M 43 C

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Since its introduction into the market, the MaK long-stroke engine series M 43 has achieved an outstanding position on the marine applications market as an in-line engine in 6, 7, 8 and 9 cylinder versions. More than 650 engines with a total power of more than 6,500 MW have already been sold making the M 43 the market leader in the 5–9 MW power class. All the cylinder configurations have contributed to this market success. More than 90% of the marine engines run on heavy fuel within IMO regulatory limits.

Power Rating

  • Power Range 6000 - 9450 kW 6000 - 9450 kW

Engine Specifications

  • Speed Range 500-514 rpm 500-514 rpm
  • Emissions IMO II IMO II
  • Aspiration Turbocharged Turbocharged
  • Bore 16.93 in 430.0 mm
  • Stroke 24.02 in 610.0 mm
  • Rotation from Flywheel End Counterclockwise / Clockwise Counterclockwise / Clockwise
  • Configuration 6,7,8,9 Cylinder 6,7,8,9 Cylinder
  • Swept Volume 5406.7 in³ 88.6 l/cyl

Dimensions & Weights

  • Minimum Dry Weight 200620.7 lb 91.0 ton (US)
  • Minimum Length 325.6 in 8271.0 mm
  • Maximum Length 414.5 in 10528.0 mm
  • Minimum Height 202.0 in 5130.0 mm
  • Maximum Height 216.6 in 5501.0 mm
  • Minimum Width 113.3 in 2878.0 mm
  • Maximum Width 113.3 in 2878.0 mm

Engine with high safety level

The M 43 C is an engine with a high safety level, not only inside in terms of component life and availability but also with regard to external peripheral safety. SOLAS regulations are consistently observed. There is an explosion protection cover for the engine block, cladding for the complete fuel system from fuel filter to injection pump, while the exhaust gas and turbine casing, including the exhaust gas outlet casing, is in stainless steel - all part of an overall safety concept for the exhaust gas manifold.

The turbocharger group consists of a high-performance turbocharger, a cartridge-type air cooler casing and charge air cooler

The cast charge air cooler casing forms a secure foundation for the turbocharger. The rigidity of the casing and a 40% increase in the base area for the turbo - charger fastening ensure reliable, low vibration operation.

The governor drive

The governor drive is of simple and robust design. The straight-tooth gearwheel drive is safe and requires no further adjustment. Designed as a complete module.

The media duct system

The media duct system is integrated into the components wherever possible. External pipework has been reduced to a minimum. Maintenance requirements have been cut and work simplified by plug-in pipe connections.

The turning device

The turning device is of compact construction, safely flanged onto the engine block. An irreversible gear and an engagement unit ensure simple operation and increased operational safety.

The engine block

The engine block consists of compact nodular cast iron components. There is a large inspection opening for sideways removal of the crankshaft vibration damper. Increased rigidity has been achieved by means of an integrated pump mounting plate. Fewer components mean fewer areas for sealing.

Control stand with monitoring components

All the engine performance data can be simply inspected on a new control stand arrangement with reliable, analog displays. The monitoring components are arranged centrally, directly above the control stand. This ensures increased operating convenience and simplified maintenance.

Lower valve drive and injection pump drive

Lower valve drive and injection pump drive “Keep it simple” - this design prin ciple is consistently applied in this component. Of modular construction, the component is of simple and robust design and boasts increased operational safety because no ad justment work is necessary.

Cooled injection nozzle

Cooled injection nozzles The design of the cooled injection nozzle provides a number of advantages, particularly during heavy fuel operation.

M 43 C Standard Equipment

Air Inlet System

  • Air intake silencer / filter

Control System

  • Load sharing unit (for multiple engine plant only)
  • Protection panel (emergency stop, override, reset push buttons)
  • Protection system
  • Serial link interface (MODbus / canbus)
  • Speed governor
  • Start / stop panel

Cooling System

  • Electronic cooling water preheater
  • HT cooling water pump (engine driven)
  • 2-stage charge air cooler

Exhaust System

  • Exhaust gas expansion joint
  • Exhaust gas insulated manifolds
  • Turbocharger at flywheel end

Fuel System

  • Fuel circulating pump (electric driven / for MGO/MDO only)
  • Fuel indicator filter
  • Fuel pressure valve (separate / for MGO/MDO only)


  • Control push buttons and lamps
  • Emergency stop lever
  • Local control panel
  • Pressure and temperature indicator

Lube System

  • Dry sump
  • Lube oil duplex filter
  • Lube oil plate cooler (separate)
  • Lube oil pump (engine driven)
  • Lube oil self-cleaning filter
  • Pressure regulating valve

Mounting System

  • High flexible coupling
  • Rigid mounting

Starting System

  • Electrical barring device
  • Starting air valve


  • Lifting device (rental)
  • Torsional Vibration Calculation (TVC)

M 43 C Optional Equipment

Air Inlet System

  • Air inlet shut-off valve
  • Air intake transition piece
  • Expansion joint
  • Silencer / filter

Control System

  • Electronic speed governor cabinet
  • Engine alarm system
  • Remote control system
  • Remote indicators (start air pressure, engine speed, etc.)
  • Starter for electric driven pumps
  • 24 DC UPS

Cooling System

  • FW/SW plate cooler
  • HT cooling water pump (electric driven)
  • LT cooling water pump (electric driven)
  • Sea water cooling pump (electric driven)
  • Steam/thermal oil cooling water preheater
  • Temperature control valve

Exhaust System

  • Silencer (with or without spark arrestor)
  • Turbocharger at counter-flywheel side

Fuel System

  • Fuel oil cooler
  • HFO final preheater
  • HFO pressure regulating valve
  • HFO self-cleaning automatic filter
  • HFO supply and booster pumps (electrical driven)
  • HFO treatment and supply modules
  • HFO viscosity control device
  • Mixing tank

Lube System

  • Lube oil pump (electrical driven)
  • Lube oil treatment and combined modules
  • Pre-lubricating oil pump (electrical driven)
  • Temperature control valve

Mounting System

  • Flexible pipe connections
  • Resilient mounting

Starting System

  • Starting air compressor
  • Starting air receiver


  • Cat Propulsion Systems
  • Engine PTO coupling
  • PTO alternator
  • PTO shaft on counter-flywheel side
  • Reduction gear
  • Reduction gear PTO coupling

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