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The Cat® C18 ACERT marine propulsion engine packs more of what you need without adding size and weight. So you can take more offshore without taking more on-board. Along with proven Caterpillar reliability and durability, the C18 ACERT offers expanded power capabilities with virtually smoke-free operation, maintaining a smaller impact on the environment. Caterpillar is dedicated to providing long-term solutions for our customers and for the environment. Exclusive ACERT Technology optimizes fuel economy, performance, and emission control, meeting the latest emissions standards: Commercial Marine EPA Tier 2, CCNR Stage II, EU Stage IIIa Inland waterway, IMO by GL and ABS.

Power Rating

Continuous Ratings - Maximum Power 600.0 bhp 447.0 bkW Less
Heavy Duty Ratings - Maximum Power 670.0 bhp 500.0 bkW Less
Maximum Continuous Ratings - Maximum Power 715.0 bhp 533.0 bkW Less

Engine Specifications

Configuration In-line 6, 4-Stroke-Cycle Diesel In-line 6, 4-Stroke-Cycle Diesel Less
Stroke 7.2 in 183.0 mm Less
Displacement 1106.0 in3 18.1 L Less
Rotation (from flywheel end) Counterclockwise Counterclockwise Less
Bore 5.7 in 145.0 mm Less
Aspiration TA, TTA TA, TTA Less

Dimensions & Weights

Minimum Dry Weight 3700.0 lb 1678.0 kg Less
Maximum Length 62.6 in 1591.0 mm Less
Maximum Width 44.0 in 1118.0 mm Less
Minimum Height 45.0 in 1144.0 mm Less
Minimum Length 59.2 in 1505.0 mm Less
Minimum Width 42.1 in 1068.0 mm Less
Maximum Height 46.5 in 1182.0 mm Less

More Comprehensive Control

For optimum performance and reliability, leverage exclusive Caterpillar engine control and monitoring systems, specifically designed for Cat electronic marine propulsion engines.

Cat ADEM A4 Electronic Control Unit (ECU)

The Cat ADEM A4 Electronic Control Unit (ECU)provides the most advanced engine intelligence available, maintaining peak performance with enhanced fault tracking and troubleshooting.

More precise fuel delivery

The Mechanically actuated Electronically controlled Unit Injector (MEUI) fuel system provides variable injection timing and duration to optimize combustion at any given speed and load. This proven fuel system technology is the result of more than 20 years of Caterpillar experience and leadership in revolutionary fuel system design.

More peace of mind

The C18 ACERT is available directly from our factory in Marine Classification Society (MCS) approved packages, meeting: ABS/DNV/LR/RMRS/BV/GL/CCS/RINa

C18 ACERT Tier 2 Standard Equipment

Air Inlet System
  • Aftercooler - sea water, corrosion resistant
  • Air cleaner/fumes disposal (closed system)
  • Turbocharger, jacket water cooled
  • Turbocharger inlet, 152 mm (6 in) OD straight connection

Exhaust System
  • Manifold & Turbocharger, watercooled
  • 152 mm (6 in) round flanged outlet

Fuel System
  • Fuel filter, RH service on Port, LH service on Starboard
  • Fuel transfer pump
  • Fuel priming pump
  • Flexible fuel lines

  • Electronic service meter, instrument panel (24V), start/stop switch, emergency stop button, maintenance due light, diagnostic light, warning light, maintenance clear switch, start motor magnetic switch, 15 and 3A breakers

Lube System
  • Crankcase breather; oil cooler; spin-on oil filter, RH service on port, LH service on starboard; center sump deep oil pan; oil filler; dipstick, RH service on port, LH service on starboard; gear-driven oil pump

Mounting System
  • Front support - adjustable

Power Takeoffs
  • Hydraulic pump drive, SAE A, 11 tooth spline
  • Crankshaft pulley, 292 mm (11.5 in) two groove, 15.88 mm (.63 in) width
  • 46 ft-lbs max torque, counterclockwise as viewed from the front of the engine looking into the drive and it turns 1.41 x engine speed

Protection System
  • A4 ECU Electronic Monitoring System provides customer programmable engine de-rate strategies to protect against adverse operating conditions

  • Vibration damper
  • Lifting eyes
  • RH or LH service options
  • Literature
  • Upper rear-facing customer wiring connector and Service Tool connection

Flywheel and Flywheel Housing
  • Flywheel, SAE No. 1, 113 teeth
  • Flywheel housing, SAE No. 1
  • SAE standard rotation
  • Flywheel, SAE No. 0, 136 teeth
  • SAE standard rotation

Control System
  • Electronic governing
  • Programmable low idle
  • Electronic diagnostics and fault logging
  • Engine and transmission monitoring(speed,temperature,pressure)
  • Fuel/air ratio control

Cooling System
  • Thermostat and housing
  • Jacket water pump, gear driven
  • Sea water pump, rubber impeller, self-priming, gear driven
  • Heat exchanger, titanium plate with expansion tank (heat exchanger models only)

  • 2007 EPA Marine Tier 2 Commercial Emissions standards.
  • EU Stage IIIa Inland Waterway (directive 97/68/EC)
  • CCNR Stage II

C18 ACERT Tier 2 Optional Equipment

Air Inlet System
  • Air Cleaner – Regular duty
  • Aftercooler Condensate drain

Charging System
  • Battery Charger, 10A
  • Charging Alternator, 24V 60A
  • Ammeter Gauge—24V

Cooling System
  • Rubber Impeller Sea Water Pump w/ 110 deg inlet (D Rating)

Exhaust System
  • Dry Elbow
  • Dual Dry Elbow (D Rating)
  • Watercooled Elbow
  • Flexible Fittings
  • Outlet Flange
  • Water Lines
  • Muffler
  • Muffler Spark Arresting
  • Flange

Flywheels & Flywheel Housing
  • SAE #0 – RH and LH Service

Fuel System
  • Primary fuel filter
  • Primary Fuel/Water Separator
  • Duplex Fuel Filters
  • Fuel Cooler (Hex)

  • Variable Engine Wiring
  • Tachometer, Digital
  • Tachometer Mounting
  • Marine Power Display
  • OEM Wiring Harness
  • Engine to Engine Harness
  • Instrument Panels
  • Wiring Harness

Lube System
  • Manual Sump Pump – RH & LH
  • Transmission Oil Cooler

Mounting System
  • Heavy Duty Front Support
  • Vibration Isolators

Power Take-Offs
  • Pulley and Damper, Crankshaft
  • Damper and Stub Shaft
  • Front Enclosed Clutch
  • Hydraulic Pump Drive Adapter

Starting System
  • Electric Starting Motors - Single 24 Volt
  • Air Starting Motor – LH
  • Jacket Water Heater, 120V or 240V
  • Battery Set — 24V, Dry
  • Air Pressure Regulator
  • Air Start Silencer

  • Damper Guard
  • Filter Cover Kit

Cat® Dealer Service

Buy any piece of Cat® equipment and also get the full support and commitment of your local Cat Dealer.

Contact your local dealer
Extended Warranty and Support

Caterpillar offers a variety of integrated solutions to help you protect your investment, minimize owning and operating costs, and maximize up-time.

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