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Cat® 3056 Diesel Marine Propulsion Engines, with ratings of 127-208 mhp (125-205 bhp) at 2100-2600 rpm, meet IMO I and EU RDC emission standards. The 3056 engine is one of the most compact packages in its class with outstanding reliability and durability. This versatile, powerful engine can be applied in single or twin engine work boat, fish boat, passenger ferry, patrol craft, or pleasure craft applications. The excellent fuel consumption and 400-hour oil change interval are significant factors in the overall low operating cost.

Power Rating

Power Range 125 - 205 bhp (93 - 153 bkW) 125 - 205 bhp (93 - 153 bkW) Less
Maximum Continuous Ratings - Maximum Power 205.0 bhp 208.0 bkW Less

Engine Specifications

Speed Range 2100 - 2600 rpm 2100 - 2600 rpm Less
Emissions IMO I, EU RCD IMO I, EU RCD Less
Aspiration NA, TA NA, TA Less
Bore 3.94 in 100.0 mm Less
Stroke 5.0 in 127.0 mm Less
Displacement 365.0 in3 6.0 L Less
Rotation (from flywheel end) Counterclockwise Counterclockwise Less
Configuration In-line 6, 4-Stroke-Cycle Diesel In-line 6, 4-Stroke-Cycle Diesel Less

Dimensions & Weights

Minimum Dry Weight 1312.0 lb 595.0 kg Less
Minimum Length 42.05 in 1068.0 mm Less
Maximum Length 42.05 in 1068.0 mm Less
Minimum Height 31.5 in 801.0 mm Less
Maximum Height 31.5 in 801.0 mm Less
Minimum Width 25.4 in 645.0 mm Less
Maximum Width 30.6 in 779.0 mm Less

IMO Emissions Compliant

DITA enginecomplies to current regulations with thecapability of meeting proposed futurelegislation.

High Quality Reliable Product

The 3056is approved by major marine classificationsocieties, and is designed to provide yearsof dependable service.

Low Operating Costs

Excellent fueleconomy and the 400-hour oil changeinterval make the 3056 very economical tooperate.

Environmentally Friendly

The cold starttiming advance mechanism reduces whitesmoke at start-up. The controlledexpansion piston and low friction ring packare designed to control oil consumption.These features directly contribute to easiercold starting and lower emissions at idleand operating speeds.

Flexible Installation

The 3056 designallows multiple installation angle capabilityfor a variety of vessels from +17° to -5°(requires optional Engine Front Down Kit),with a maximum 30° vessel operatingangle. Multi-groove crankshaft pulley hastwo available grooves for PTO drives whichadds to the compactness of engine.Multi-option exhaust outlets provide themost suitable cost-effective design foreach installation including repowers. Theheight of the mounting feet can beadjusted to make installation easy.

Cost Effective Core Engines

The highvolume production provides more costeffective core engines with reduceddelivery time.

Specialized High Quality Marinization

Complete propulsion packages aredesigned to meet customer requirements.

Powerful and Efficient

The directinjection combustion system with rotaryfuel pump and two valves per cylinder improves combustion efficiency andprovides more power and torque withlower fuel consumption, thus reducingoperating costs. The lightweightcomponent design of the compositeexpansion tank and air filter intakeimproves engine power-to-weight ratioand is more cost effective.

Outstanding Performance

Thewastegated turbocharger on the 205 hpengine develops more horsepower at lowerengine speeds for more vessel acceleration.The dry insulation on the turbochargerimproves engine performance and is morecost effective. The insulation lowers thesurface temperature of the turbochargerand improves safety.

Reliable and Durable Component Design

The positive drive gear-driven jacketwater and sea water pump provide greaterreliability and lower operating costs. Thehelically cut gear train contributes to theacoustically tuned mechanical structure ofthe engine to provide lower engine noiseand quieter overall operation.The plate-type oil cooler has no waterpipes or connections and is less likely todevelop leaks. The replaceable valve seatinserts and guides extend service life forlong term reliability and delay majorcomponent replacement.Watercooled exhaust manifolds reducethe possibility of corrosion and fire.The fuel shutoff solenoid (ETS) withmanual override lever is built into the fuelpump with no external linkage for safereliable operation at no extra cost.Insulated electrical components reducefire hazards and corrosion with nosacrificial anodes required. The sea waterstrainer protects the aftercooler fromdebris and potential overheating andimproves reliability.

3056 Standard Equipment

Air Inlet System
  • Air Cleaner/Fumes Disposal (closed system)
  • Aftercooler (sea water) (DITA)
  • Dry Insulated Turbocharger (DITA)
  • Thermostart Air Inlet Heater

Control System
  • Mechanical Governor

Exhaust System
  • Dry Insulated Turbocharger (DITA)
  • Water Cooled Exhaust Manifold

Fuel System
  • Twin Fuel Filter

Lube System
  • Crankcase Breather (closed system)
  • Twin Oil Filter
  • Engine Mounted Oil Sump Drain Pump
  • RH Service Oil Level Gauge

Power Takeoffs
  • Hydraulic pump drive, SAE A, 11 tooth spline, 46 ft-lb max torque, conterclockwise as viewed from front of the engine looking into the drive and turns 1.41 x engine speed, 292 mm crankshaft pulley, 15.88 mm width

  • Vibration Damper
  • Vibration DamperPlastic Wrap Packaging
  • Lifting Eyes
  • English Literature

Flywheel and Flywheel Housing
  • SAE No. 3 flywheel
  • SAE No. 3 flywheel housing

Cooling System
  • Gear Driven Centrifugal Jacket Water Pump
  • Gear Driven Self-priming Sea Water Pump (DITA and DINA HeatExchanger arrangements and DITA Keel Cooled arrangements)
  • Heat Exchanger with Cupro-Nickel Tube Bundle(Heat Exchanger cooled arrangements)
  • De-aeration Expansion Tank
  • Keel Cooling Connections (Keel cooled arrangements)
  • Integral Plate-Type Engine Oil Cooler
  • Sea Water Strainer (DITA)
  • Transmission Oil Cooler (DINA)
  • Thermostat and Housing
  • NOTE: Engines for keel cooling do not include keel cooler

3056 Optional Equipment

Cooling System
  • Engine Front Down Kit

Fuel System
  • Flexible Fuel Lines
  • Water Separator/Flex Fuel Lines
  • Double Wall Fuel Lines and Drain

Mounting System
  • Flexible Mounts

Marine Transmissions & Attachments
  • Marine Transmission Output Couplings
  • Flexible Coupling
  • Solid Half Coupling
  • Flexible with Mating Solid Half Coupling

  • Cruise Kits


Special Tests
  • Standard Engine Test - 3000 Family

  • Storage Preservation
  • Export Packing - Individual Engine Shipments
  • Export Packing - 20' Container Shipments
  • Export Packing - 40' Container Shipments

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Extended Warranty and Support

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