Propulsion engines
C18
The Cat® C18 commercial propulsion engine is built to deliver reliable, high-output power for workboats operating in demanding marine environments. Its inline 6-cylinder, four-stroke diesel design provides the durability and performance needed for long hours, heavy-duty duty cycles and consistent propulsion. Supported by the global Cat dealer network, the C18 helps keep vessels productive, serviceable and ready for the next job.
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Power Range
- Delivers 454–803 bhp across a wide 1800–2100 rpm operating range, giving workboat operators flexible propulsion performance for changing vessel demands and duty cycles.
Inline 6 Design
- The 18.1 L inline 6 diesel platform uses a 145 × 183 mm bore and stroke with turbocharging and separate circuit aftercooling to support sustained commercial output.
Cooling Options
- Available heat exchanger and keel cooled configurations help simplify integration across different hull designs, operating environments and vessel requirements.
Emissions Compliance
- Meets U.S. EPA Tier 3, IMO II, EU Stage V and China II standards, helping fleets operate across regulated waterways and global workboat applications.
Compact Footprint
- A 73 in 1854 mm engine length and under 4000 lb dry weight help support installation in space constrained workboat engine rooms and repower applications.
Smart Monitoring
- Electronic diagnostics and fault logging monitor engine and transmission speed, temperature and pressure, helping crews support proactive fleet management and uptime.
Versatile Power for Workboat Duty
Flexible Installation Options
Supported for Maximum Uptime
| Power Range | 454 - 1136 bhp (339 - 847 bkW) |
|---|
| Application | Workboat |
|---|---|
| Speed Range | 1800 - 2100 rpm |
| Emissions | U.S. EPA Tier 3 Commercial, IMO II, EU Stage V, China II |
| Aspiration | Turbocharged - Aftercooled |
| Bore | 5.7 in |
| Stroke | 7.2 in |
| Displacement | 1106.0 in³ |
| Rotation from Flywheel End | Counterclockwise |
| Oil Change Interval | 250 / 500 |
| Refill Capacity | 49 / 68 l |
| Configuration | In-line 6, 4-Stroke-Cycle Diesel |
| Cooling | Heat Exchanger or Keel Cooled |
| Governor | Electronic |
| Flywheel Housing | SAE No. 0 (136 teeth) or SAE No. 1 (113 teeth) |
| Minimum Dry Weight | 4000.0 lb |
|---|---|
| Minimum Length | 73.0 in |
| Minimum Height | 47.2 in |
| Maximum Height | 51.2 in |
| Minimum Width | 44.6 in |
| Maximum Width | 47.4 in |
AIR INLET SYSTEM
- Separate circuit after-cooled (SCAC)
- Open Crankcase Ventilation (OCV) system
- Turbocharger, jacket water cooled
- Turbocharger inlet, 152 mm (6 in) OD straight connection
- Air Start Accessories
COOLING SYSTEM
- Separate Circuit After-Cooling (SCAC) for both HEX and Keel cooled engines
- Engine JW and SCAC Shell & Tube Heat Exchangers for HEX cooled engines
- SCAC pump, gear driven, for HEX cooled engines only
- Jacket water pump, gear driven
- Sea water pump, bronze impeller, gear driven
- SCAC and JW shunt tanks for maintaining proper pump inlet pressures
EXHAUST SYSTEM
- Water-cooled exhaust manifold & turbocharger
- 152 mm (6 in) round flanged outlet
FLYWHEELS & FLYWHEEL HOUSINGS
- SAE No. 0, Flywheel SAE. 18, 136 teeth
- SAE No. 1, Flywheel: 14 inch, 113 teeth
FUEL SYSTEM
- Front service simplex fuel system
- Fuel transfer pump, gear driven
- Manual fuel priming pump
- Hybrid fuel line design
LUBE SYSTEM
- Front service simplex oil system
- Center sump oil pan: Deep 500 hour oil change interval, Shallow 250 hour oil change interval
- Front and top service oil filler locations
- Front service dipstick
- Oil pump, gear driven
MOUNTING SYSTEM
- Front support - adjustable
POWER TAKE-OFFS
- Poly-V groove for alternator drive
- NOTE: There are no standard power take-offs available
GENERAL
- Front damper guard
- Front service engine
- Common electrical bonding point
- Engine does not ship with zinc components
CONTROL SYSTEM
- Programmable low idle
- WOSR (Wide Operating Speed Range) available for EPA Tier 3 - B and C Ratings
- Adjustable High Idle (TEL) - EPA Tier 3 WOSR Ratings Only
- Electronic diagnostics and fault logging
- Engine and transmission monitoring (speed, temperature, pressure)
- Electronic fuel/air ratio control
- Engine Protection Mode for extended ambient conditions - EPA Tier 3 Ratings Only
- 70-pin customer connector
- Three types of throttle inputs (primary/ secondary PWM, 0-5V, 4-20mA +/-
Need installed dimensions with enclosure and tank? See Model Configurations
