"> Caterpillar MaK 9L M20C
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Caterpillar MaK

9L M20C

The Caterpillar MaK 9L M20C is a medium‑speed (900–1000 rpm) 4‑stroke marine diesel main engine delivering up to 1 665 kW, notable for its fuel flexibility (HFO, MDO, MGO) and proven reliability in ferry and offshore support applications.

1665.0 kW
Power

Engine Specifications

9
Cylinders
200 mm
Bore
300 mm
Stroke
1,665 kW
MCR Power
1000.0 rpm
MCR RPM
4-stroke
Stroke Type
Family: Caterpillar/MAK M20C/M25C/M32C/M43C · Tier: IMO Tier II · Fuel: HFO, MDO, MGO

Other Cylinder Configurations 35

4L20
4 cyl · 800 kW
6L M20C
6 cyl · 1,110 kW
6L M25C
6 cyl · 2,040 kW
6L M32C
6 cyl · 3,360 kW
6L20
6 cyl · 1,200 kW
6L32
6 cyl · 3,480 kW
6M M43C
6 cyl · 6,060 kW
6M M46DF
6 cyl · 6,600 kW
Cat C280-6
6 cyl · 2,100 kW
8L M20C
8 cyl · 1,480 kW
8L M25C
8 cyl · 2,720 kW
8L M32C
8 cyl · 4,480 kW
8L20
8 cyl · 1,600 kW
8L32
8 cyl · 4,640 kW
8M M43C
8 cyl · 8,080 kW
8M M46DF
8 cyl · 8,800 kW
Cat 3508B
8 cyl · 560 kW
Cat C280-8
8 cyl · 2,800 kW
9L M25C
9 cyl · 3,060 kW
9L M32C
9 cyl · 5,040 kW
9L20
9 cyl · 1,800 kW
9L32
9 cyl · 5,220 kW
9M M43C
9 cyl · 9,090 kW
9M M46DF
9 cyl · 9,900 kW
12V M43C
12 cyl · 12,120 kW
12V M46DF
12 cyl · 13,200 kW
12V32
12 cyl · 6,960 kW
Cat 3512B
12 cyl · 840 kW
Cat 3512C
12 cyl · 895 kW
Cat C280-12
12 cyl · 4,200 kW
16V32
16 cyl · 9,280 kW
Cat 3516B
16 cyl · 1,120 kW
Cat 3516C
16 cyl · 1,200 kW
Cat 3516E
16 cyl · 1,305 kW
Cat C280-16
16 cyl · 5,600 kW

Components & Design

Component data being added…

Technical Data

Bore/Stroke ratio 200/300 mm (ratio 1:1.5)
BMEP (Brake Mean Effective Pressure) 24.1 bar @ 900 rpm, 24.2 bar @ 1000 rpm
SFOC (Specific Fuel Oil Consumption) 186-190 g/kWh @ 100%/85% MCR
Specific oil consumption 0.6 g/kWh (tolerance ±0.3 g/kWh)
Swept volume per cylinder 9.4 liters
Power per cylinder 170-190 kW
Mean piston speed 9-10 m/s @ 900/1000 rpm
Turbocharger system KBB HPR4000/5000, high-performance, non-water-cooled casing with high charge air delivery
Charge air cooler Redesigned for M20C, integrated with cooling system
Fuel injection system Direct injection, high-pressure common rail capable
Cylinder liner Anti-wear ring design, piston removal interval 30,000 hours under HFO operation
Genset frequency stability Frequency drop <5% in 4-load step system (testbed confirmed)
unified from engine model True

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Common failures & inspection points

Charge air cooler fouling – oil-bearing deposits, pressure drop, temperature rise after cooler, turbocharger stall risk

Charge air cooler check for fouling, measure pressure drop before/after cooler, monitor air inlet temperature after cooler (should not exceed setpoint); during HFO operation: plan regular flushing/cleaning

Turbocharger erosion from exhaust gas particles – particularly during HFO operation; metal particles in exhaust damage turbine wheel

Measure turbocharger vibrations, check exhaust temperature differs per cylinder (can indicate erosion), turbocharger wear inspection every 40,000 hours

Crankshaft main bearing wear – main bearings and connecting rod bearings; wear >0.05 mm requires replacement

Measure bearing shell thickness and compare with setpoint (difference <0.05 mm acceptable), check bearing pressure, document bearing clearance in inspection report

Fuel injection system leakage and wear – deviations in injection pressure, poor atomization lead to soot formation

Inspection required at 15,000 operating hours: remove and inspect all injection pumps, check opening pressure (specification in manual), check needle valves for wear

Camshaft bearing damage and wear – pressure drop at camshaft bearings leads to valve train clearance

Measure lubricating oil pressures at camshaft bearing (setpoint in handbook), valve clearance control at 1,500 operating hours, monitor vibrations/noise from valve train

Type-general inspection and maintenance points for this equipment category — not model-specific.

Suppliers & Spare Parts

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Manuals

  • operating
    MaK M43C Operating Manual
    Caterpillar Marine / MaK
  • maintenance
    MaK M43C Maintenance Manual
    Caterpillar Marine / MaK
  • spare_parts
    MaK M43C Spare Parts Catalogue
    Caterpillar Marine / MaK
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Equipment Model #38072 · ✓ still in production