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Specs For Cummins Marine Engines
Cummins 4BTA
Application: Marine
This engine is commonly used in a wide range of marine applications where reliability, compact size, and steady torque delivery are critical. Typical installations include small commercial fishing vessels, trawlers, sailboats, pilot-style utility boats, patrol craft, and auxiliary propulsion or generator applications. Its compact footprint and moderate weight make it a strong candidate for repowers, particularly in vessels with limited engine room space or weight constraints.
Power Output: 150–155 hp @ 2800 rpm
This horsepower range is well suited for light- to medium-duty marine propulsion. It provides sufficient power for efficient cruising while remaining compatible with smaller marine gearboxes and shafting, helping reduce drivetrain stress and extend component life.
Torque Range: 380–597 Nm (280–440 ft-lb)
Strong low- and mid-range torque allows the engine to perform well in displacement and semi-displacement hulls. This torque curve supports smooth acceleration, reliable maneuvering at low speed, and steady performance under continuous marine load.
Engine Weight: 360 kg (794 lb)
The relatively low engine weight simplifies installation and helps maintain proper vessel trim. This is particularly beneficial in sailboats and smaller commercial vessels where weight distribution is critical.
Standard Engine Oil Capacity: 10.4 liters (11 qt)
Sufficient oil capacity supports extended run times common in marine operation, providing stable lubrication and improved thermal control during long cruises or work cycles.
Cooling System Capacity: 17.4 liters (18.4 qt)
The cooling system capacity supports effective heat management when paired with a marine heat exchanger and raw water system, ensuring stable temperatures in saltwater and warm-climate operation.
Typical Marine Transmission Pairings
This engine is commonly paired with light- to medium-duty marine transmissions such as:
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Twin Disc MG502 and MG506 series
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ZF/Hurth marine gears (ZF 45, ZF 63, and similar models)
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Velvet Drive marine transmissions in appropriate ratios
These gearboxes complement the engine’s RPM and torque characteristics, providing smooth engagement, reliable power transfer, and flexibility in propeller selection for various vessel types.
Cummins 6BT
Application: Marine
The Cummins 6BT is one of the most widely used and respected marine diesel engines in the world. It is commonly found in commercial fishing vessels, trawlers, patrol boats, pilot-style utility boats, crew boats, and heavy recreational yachts. Its reputation for durability, mechanical simplicity, and excellent torque characteristics makes it a preferred choice for both new installations and repower projects. The 6BT performs especially well in displacement and semi-displacement hulls that operate under sustained load.
Power Output: 210–220 hp @ 2600 rpm
This power range places the 6BT firmly in the medium-duty marine category. It provides strong propulsion capability while maintaining conservative operating speeds, which helps reduce wear and extend engine life. The lower rated RPM compared to smaller engines also pairs well with larger propellers for improved efficiency.
Torque Range: 542–827 Nm (400–610 ft-lb)
The Cummins 6BT is known for its strong low-end and mid-range torque. This broad torque curve is ideal for pushing heavier vessels, towing loads, and maintaining steady cruise speeds in rough sea conditions. High torque output supports smooth acceleration and excellent control at low speeds.
Engine Weight: 465 kg (1,025 lb)
The heavier weight reflects the 6BT’s robust block and rotating assembly. While heavier than smaller engines, this weight contributes to durability and long service life. Proper engine bed support and alignment are important considerations in marine installations.
Standard Engine Oil Capacity: 15 liters (16 qt)
The larger oil capacity supports extended service intervals and effective lubrication during long operating hours, common in commercial and offshore marine use.
Cooling System Capacity: 20.6 liters (21.6 qt)
A generous cooling capacity allows the 6BT to maintain stable operating temperatures when paired with marine heat exchangers and raw water cooling systems, even under continuous load.
Typical Marine Transmission Pairings
The Cummins 6BT is commonly paired with medium-duty marine transmissions such as:
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Twin Disc MG502, MG506, and MG508 series
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ZF marine gears (ZF 63A, ZF 68A, ZF 80)
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Velvet Drive HD marine transmissions
These transmissions match well with the 6BT’s torque output and RPM range, allowing flexible gear ratios and efficient propeller selection across a wide range of vessel types.
Cummins 6BTA
Application: Marine
The Cummins 6BTA is a high-output evolution of the 6BT platform, widely used in commercial fishing vessels, fast trawlers, patrol craft, crew boats, and performance-oriented workboats. With turbocharging and aftercooling, the 6BTA delivers higher horsepower while retaining the durability and serviceability Cummins is known for. It is well suited for semi-displacement and planing hulls that require strong acceleration and sustained cruise power.
Cummins 6BTA – Marine Power Ratings
260–270 hp @ 2600 rpm
Peak Torque @ 1600 rpm: 922 Nm (680 ft-lb)
This rating is commonly used in commercial and light-duty fleet applications where strong low-RPM torque and fuel efficiency are priorities.
315–330 hp @ 2800 rpm
Peak Torque @ 2000 rpm: 931 Nm (687 ft-lb)
This mid-range configuration balances higher cruise speeds with manageable thermal and drivetrain loads, making it popular in patrol and utility vessels.
355–370 hp @ 3000 rpm
Rated Torque: 842 Nm (620 ft-lb)
Peak Torque @ 2200 rpm: 992 Nm (732 ft-lb)
The highest-output marine rating is typically found in performance workboats and fast commercial vessels where speed and acceleration are critical.
Engine Weight: 465 kg (1,025 lb)
The robust construction supports higher cylinder pressures associated with aftercooled operation while maintaining long service life when properly cooled and maintained.
Standard Engine Oil Capacity: 15 liters (16 qt)
Adequate oil capacity supports thermal control and lubrication during extended marine run times.
Cooling System Capacity: 20.6 liters (21.6 qt)
Designed to manage the increased heat load from higher horsepower ratings when paired with marine heat exchangers and raw water systems.
Typical Marine Transmission Pairings
The Cummins 6BTA is commonly paired with:
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Twin Disc MG506, MG508, and MG511 series
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ZF marine gears (ZF 63A, ZF 68A, ZF 85)
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Heavy-duty Velvet Drive marine transmissions
These gearboxes complement the 6BTA’s higher torque output and operating RPM, allowing efficient power transfer across a range of vessel types.
Cummins QSB 5.9
Application: Marine
The Cummins QSB 5.9 is a high-performance marine diesel designed for planing hulls, fast commercial vessels, patrol craft, crew boats, and high-speed recreational yachts. As an electronically controlled evolution of the 5.9-liter platform, the QSB 5.9 delivers significantly higher horsepower while maintaining a compact footprint, making it well suited for repower projects where space is limited but performance demands are high.
Cummins QSB 5.9 – Marine Power Ratings
425 hp @ 3000 rpm
Peak Torque @ 2000 rpm: 1,220 Nm (900 ft-lb)
This rating provides strong mid-range torque and responsive acceleration, ideal for vessels that require quick planing and sustained cruise speeds without excessive engine weight.
480 hp @ 3400 rpm
Peak Torque @ 2200 rpm: 1,274 Nm (940 ft-lb)
The higher-output configuration is typically used in fast patrol vessels, performance workboats, and sportfishing boats where top-end speed and throttle response are critical.
Engine Weight: 658 kg (1,450 lb)
The increased weight reflects the QSB 5.9’s robust block, electronic fuel system, and high-output turbocharging components, all designed to support higher cylinder pressures and sustained marine operation.
Standard Engine Oil Capacity: 15.1 liters (16 qt)
This oil capacity supports effective lubrication and heat control during high-RPM operation common in planing applications.
Cooling System Capacity: 25–27 liters (26–28.5 qt)
A larger cooling capacity helps manage the significant thermal load generated at higher horsepower ratings, ensuring stable operating temperatures when paired with marine heat exchangers and raw water cooling systems.
Cummins QSB 6.7
Application: Marine
The Cummins QSB 6.7 is a versatile, electronically controlled marine diesel designed for a wide range of commercial vessels, patrol craft, crew boats, pilot-style utility boats, fast trawlers, and larger recreational yachts. Known for its strong torque output and modern emissions-compliant design, the QSB 6.7 performs well in both displacement and planing hulls, offering reliable power delivery across multiple duty ratings.
Cummins QSB 6.7 – Marine Power Ratings
250 hp @ 2600 rpm
Rated Torque: 676 Nm (499 ft-lb)
Peak Torque @ 1600 rpm: 983 Nm (725 ft-lb)
This lower output rating is commonly used in commercial and light-duty fleet applications where fuel efficiency, longevity, and steady cruise operation are priorities.
305 hp @ 2600 rpm
Rated Torque: 824 Nm (608 ft-lb)
Peak Torque @ 1700 rpm: 1,174 Nm (866 ft-lb)
A balanced configuration that supports higher cruise speeds while maintaining manageable thermal and drivetrain loads.
380 hp @ 3000 rpm
Rated Torque: 890 Nm (657 ft-lb)
Peak Torque @ 2000 rpm: 1,335 Nm (985 ft-lb)
This rating is often selected for faster commercial vessels and recreational boats requiring strong acceleration and sustained high-speed operation.
425 hp @ 3000 rpm
Rated Torque: 995 Nm (734 ft-lb)
Peak Torque @ 2000 rpm: 1,424 Nm (1,050 ft-lb)
The highest-output marine rating delivers exceptional torque for planing hulls and high-performance applications where throttle response and top-end speed are critical.
Engine Weight: 658 kg (1,450 lb)
The consistent engine weight across ratings reflects the QSB 6.7’s robust block, high-pressure fuel system, and reinforced internal components designed to handle elevated power outputs.
Standard Engine Oil Capacity: 15.1 liters (16 qt)
Adequate oil capacity supports lubrication stability and heat management during extended marine run times.
Cooling System Capacity: 26.5 liters (28 qt)
A large cooling capacity helps manage thermal loads across all power ratings, ensuring stable operating temperatures when paired with marine heat exchangers and raw water cooling systems.
Cummins 6CTA
Application: Marine
The Cummins 6CTA is a heavy-duty marine diesel widely used in commercial fishing vessels, offshore workboats, patrol craft, ferries, tug-assist vessels, and larger displacement yachts. Known for its strong mid-range torque and durability, the 6CTA is well suited for vessels that operate under continuous load and require dependable power rather than high-RPM performance. Its larger displacement and cooling capacity make it a popular choice for commercial-duty propulsion and long-hour service.
Cummins 6CTA – Marine Power Ratings
255 hp @ 1800 rpm
Peak Torque: 1,193 Nm (880 ft-lb)
This low-speed rating is commonly used in displacement-hull vessels where fuel efficiency, longevity, and steady pushing power are critical. The lower operating RPM reduces drivetrain stress and supports extended service intervals.
350 hp @ 2500 rpm
Peak Torque: 1,125 Nm (830 ft-lb)
A mid-range configuration that balances increased cruise speed with manageable thermal and mechanical loads, making it suitable for mixed-duty commercial vessels and utility boats.
430–450 hp @ 2600 rpm
Rated Torque: 1,178 Nm (869 ft-lb)
Peak Torque @ 1800 rpm: 1,395 Nm (1,029 ft-lb)
The highest-output marine rating delivers exceptional low-end torque for heavier vessels, towing operations, and applications requiring strong acceleration under load.
Engine Weight: 712 kg (1,570 lb)
The heavier engine weight reflects the 6CTA’s robust block, reinforced rotating assembly, and heavy-duty cooling system, all designed to support high torque and long service life in commercial marine environments.
Standard Engine Oil Capacity: 21.9 liters (23.2 qt)
The larger oil capacity supports effective lubrication and thermal stability during extended run times and high-load operation.
Cooling System Capacity: 28.9 liters (30.5 qt)
A generous cooling capacity helps manage heat under continuous-duty conditions, ensuring stable operating temperatures when paired with marine heat exchangers and raw water cooling systems.
Cummins QSC
Application: Marine
The Cummins QSC is a high-performance, electronically controlled marine diesel designed for large commercial vessels, offshore workboats, fast ferries, patrol craft, crew boats, and heavy-duty yachts. Positioned above the QSB and 6CTA platforms, the QSC is built for applications that demand high horsepower, strong torque delivery, and reliable operation under sustained load. Its robust design and modern fuel system make it well suited for vessels operating at higher speeds or carrying heavy payloads.
Power Output: 500–600 hp
This horsepower range places the QSC firmly in the high-output marine category. It provides ample power for planing and semi-displacement hulls, supporting fast cruise speeds, heavy propulsion demands, and rapid acceleration. These ratings are commonly used in twin-engine installations where balanced power and redundancy are critical.
Rated Torque: 1,408 Nm (1,038 ft-lb)
Peak Torque @ 1800 rpm: 1,800 Nm (1,327 ft-lb)
The QSC’s strong torque output at relatively low RPM allows vessels to maintain speed efficiently under load. This torque characteristic is especially valuable for offshore vessels, ferries, and workboats that experience variable sea conditions and frequent throttle changes.
Engine Weight: 896 kg (1,975 lb)
The substantial engine weight reflects the QSC’s heavy-duty block, reinforced internal components, and high-capacity cooling and fuel systems. Proper engine bed design and alignment are important considerations in marine installations, particularly for twin-engine configurations.
Standard Engine Oil Capacity: 21.6 liters (5.7 gal)
The large oil capacity supports extended run times and effective lubrication under high load, helping manage heat and reduce internal wear during continuous-duty operation.
Cooling System Capacity: 25–29 liters (6.5–7.75 gal)
A high-capacity cooling system is essential for managing the thermal load produced at higher horsepower levels. When paired with marine heat exchangers and raw water cooling systems, this capacity helps ensure stable operating temperatures in demanding marine environments.
Cummins QSL
Application: Marine
The Cummins QSL is a heavy-duty marine diesel designed for commercial fishing vessels, offshore workboats, ferries, patrol vessels, tug-assist craft, and large displacement yachts. Known for its strong low-RPM torque and durability, the QSL is well suited for vessels that operate under continuous load and prioritize pushing power, fuel efficiency, and long service life over high-speed operation.
Cummins QSL – Marine Power Ratings
285 hp @ 1800 rpm
Peak Torque @ 1400 rpm: 1,332 Nm (983 ft-lb)
This lower-speed rating is commonly used in displacement-hull applications where steady propulsion, fuel efficiency, and reduced drivetrain stress are critical.
330 hp @ 1800 rpm
Peak Torque @ 1400 rpm: 1,553 Nm (1,145 ft-lb)
A mid-range configuration that provides increased torque output while maintaining conservative engine speeds, making it suitable for commercial vessels operating long duty cycles.
405 hp @ 2100 rpm
Peak Torque @ 1400 rpm: 1,619 Nm (1,194 ft-lb)
The highest-output marine rating delivers exceptional low-end torque for heavier vessels, towing operations, and applications requiring strong acceleration under load.
Engine Weight: 977 kg (2,153 lb)
The substantial engine weight reflects the QSL’s robust block, reinforced rotating assembly, and heavy-duty cooling and fuel systems designed for long-term commercial service.
Standard Engine Oil Capacity: 25.4 liters (26.8 qt)
The large oil capacity supports effective lubrication, heat management, and extended service intervals during continuous marine operation.
Cooling System Capacity: 29.3 liters (31 qt)
A high-capacity cooling system helps manage thermal loads and maintain stable operating temperatures when paired with marine heat exchangers and raw water cooling systems, even under sustained load.
Cummins QSM11
Cummins QSM11 – Marine Specifications & Versions
Application: Marine
The Cummins QSM11 in marine configuration is a high-output, electronically controlled diesel designed for large commercial vessels, offshore support vessels, fast ferries, patrol craft, crew boats, and heavy-duty workboats. Marine versions are engineered for sustained high load, rapid throttle response, and continuous-duty operation in saltwater environments.
Marine Power Ratings & Torque (QSM11)
QSM11 Marine – 610 hp Class
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Power: ~610 hp @ 2300 rpm
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Rated Torque: ~1,950 Nm (1,438 ft-lb)
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Peak Torque: ~2,200 Nm (1,620 ft-lb) @ ~1700 rpm
QSM11 Marine – 670 hp Class (High Output)
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Power: 670 hp @ 2300 rpm
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Rated Torque: 2,046 Nm (1,509 ft-lb)
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Peak Torque @ 1700 rpm: 2,373 Nm (1,750 ft-lb)
These marine ratings are commonly used in twin-engine installations for planing and semi-displacement hulls requiring high cruise speeds and strong mid-range torque.
Physical & Service Capacities (All Marine Versions)
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Engine Weight: 1,188 kg (2,620 lb)
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Standard Engine Oil Capacity: 32.9–36.7 liters (33.8–38.8 qt)
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Cooling System Capacity: 36 liters (38 qt)
The large oil and cooling capacities are designed to support long-duty cycles, high thermal loads, and stable operating temperatures under continuous marine operation.
Marine Control & Configuration Variants
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Electronic Marine QSM11 (CM570 / CM580)
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Continuous-duty marine ratings for commercial service
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High-output marine ratings for fast ferries and offshore vessels
All marine variants share the same core displacement and block architecture, with output differences driven by turbocharging, calibration, and duty rating.
Typical Marine Transmission Pairings
Due to the QSM11’s torque output, marine installations typically use heavy-duty gearboxes, including:
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Twin Disc MGX-5114, MGX-5136
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ZF Marine 5115 / 5250 / 5350 series
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Reintjes WAF / WAFI series
Transmission selection is based on torque rating, reduction ratio, vessel type, and shaft size requirements.
Cummins KTA19
Cummins KTA19 – Marine Specifications & Versions
Application: Commercial & Recreational Marine Propulsion / Auxiliary
The Cummins KTA19 is a large-displacement, mechanically governed marine diesel designed for heavy commercial propulsion, offshore service, towing, dredging, and auxiliary power generation. In marine service, the KTA19 is selected for applications requiring extreme low-RPM torque, continuous-duty capability, and long service liferather than high engine speed.
Marine Power Ratings & Torque (KTA19)
KTA19 Marine – Mid-Output Rating
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Power: 450–525 hp
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Rated Speed: ~1800 rpm
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Peak Torque @ 1500 rpm: ~2,137 Nm (1,576 ft-lb)
Commonly used in displacement hulls, auxiliary propulsion, and generator drive applications where fuel efficiency and longevity are prioritized.
KTA19 Marine – Standard Propulsion Rating
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Power: 640 hp @ 1800 rpm
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Rated Torque: 2,532 Nm (1,867 ft-lb)
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Peak Torque @ 1500 rpm: 2,830 Nm (2,087 ft-lb)
This is one of the most common marine propulsion ratings, widely used in tugboats, offshore supply vessels, large fishing vessels, ferries, and workboats.
KTA19 Marine – High-Output / Special Ratings
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Power Range: up to 700 hp
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Peak Torque Range @ 1500 rpm: up to 4,985 Nm (3,676 ft-lb)
Higher ratings are typically application-specific and paired with heavy reduction gearing and large shafting.
Physical & Service Capacities (Marine Versions)
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Engine Weight: 2,073 kg (4,570 lb)
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Standard Engine Oil Capacity: 32–72 liters (8.5–19 gal)
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Oil capacity varies by oil pan configuration
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Add 7.6 liters (2 gal) if equipped with a rear gear train
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Cooling System Capacity: 32.2 liters (34 qt)
The wide oil capacity range reflects the KTA19’s modular sump and gearing configurations commonly used in marine propulsion and auxiliary installations.
Marine Configuration Variants
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Mechanical marine KTA19 (PT fuel system)
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Propulsion ratings (1800 rpm class)
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Continuous-duty auxiliary ratings
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Single-engine and twin-engine marine installations
All marine variants share the same 19-liter displacement and block architecture, with output differences driven by turbocharging, calibration, and duty rating.
Typical Marine Transmission Pairings
Due to the KTA19’s very high torque output, marine installations use heavy-duty reduction gearboxes, including:
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Twin Disc MGX-5145 / MGX-5165 / MGX-5180 series
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ZF Marine 6000 series (ZF 6650, ZF 7500 depending on ratio)
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Reintjes WAF / WAFI series
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Masson Marine reduction gears for displacement hulls
Transmission selection is based on torque rating, reduction ratio, shaft diameter, and vessel duty cycle.
Cummins KTA38
Cummins KTA38 – Marine Specifications & Versions
Application: Marine
The Cummins KTA38 is an ultra-heavy-duty marine diesel designed for large commercial vessels, offshore support vessels, anchor handlers, tugboats, dredgers, large ferries, and high-capacity workboats. In marine service, the KTA38 is selected for applications requiring very high continuous torque at low RPM, extreme durability, and long service life under sustained load.
Marine Power Ratings & Duty Classes (1800 rpm Class)
KTA38 Marine – Continuous Duty
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Power: 1,040 hp @ 1800 rpm
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Rated Torque: ~4,747 Nm (3,501 ft-lb)
Used in vessels operating 24/7 at steady load, such as tugs, dredges, and auxiliary propulsion.
KTA38 Marine – Prime Power
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Power: 1,300 hp @ 1800 rpm
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Rated Torque: ~5,210 Nm (3,843 ft-lb) @ 1500 rpm
Common in offshore support vessels and heavy commercial propulsion where variable load is expected.
KTA38 Marine – Overload Rating
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Power: 1,430 hp @ 1800 rpm
Used for short-duration peak demands in propulsion or maneuvering-intensive operations.
Overall Marine Power Range: 850–1500 hp @ 1800 rpm
Physical & Service Capacities (Marine Versions)
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Engine Weight: 4,218 kg (9,300 lb)
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Standard Engine Oil Capacity:
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Sub-base sump: 87–114 L (23–30 gal)
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Double deep front/center sump: 140–166 L (37–44 gal)
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Double deep rear/center sump: 140–166 L (37–44 gal)
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Cooling System Capacity: 118–155 L (31.2–41 gal)
Large oil and cooling capacities are required to manage thermal loads during continuous, high-output marine operation.
Marine Configuration Variants
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Mechanical KTA38 marine propulsion engines
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Continuous, prime, and overload duty ratings
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Single-engine and twin-engine propulsion installations
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Propulsion and auxiliary drive configurations
All marine versions share the same 38-liter displacement V12 architecture, with output differences driven by turbocharging, calibration, and duty rating.
Typical Marine Transmission Pairings
Given the extreme torque output of the KTA38, marine installations require very heavy-duty reduction gearing, including:
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Twin Disc MGX-5180 / MGX-5200 series
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ZF Marine 6000 series (ZF 6650, ZF 7600)
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Reintjes WAF / WAFI heavy-duty series
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Masson Marine reduction gears for displacement and towing vessels
Transmission selection is dictated by torque capacity, reduction ratio, shaft diameter, and vessel duty cycle.
Cummins KTA50
Cummins KTA50 – Marine Specifications & Versions
Application: Commercial & Recreational Marine Propulsion
The Cummins KTA50 is an ultra-heavy-duty marine diesel designed for very large commercial vessels, offshore support vessels, anchor handlers, large tugboats, dredgers, high-speed ferries, and mega-yachts. In marine service, the KTA50 is selected for applications requiring extreme continuous torque at low RPM, high reliability under sustained load, and long overhaul intervals.
Marine Power Ratings & Duty Classes (1800 rpm Class)
Overall Marine Power Range: 1,180 – 1,875 hp @ 1800 rpm
These ratings are offered across multiple duty classes to match vessel operating profiles:
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Continuous Duty Ratings
Used for vessels operating near rated load for extended periods (tugs, dredges, offshore workboats).
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Prime / Intermittent Duty Ratings
Applied to offshore support vessels and fast ferries with variable load profiles.
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High-Output / Special Ratings
Used where short-duration peak power is required for maneuvering, acceleration, or heavy towing.
Peak Torque Range @ 1800 rpm:
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5,603 – 6,747 Nm (4,132 – 4,976 ft-lb)
The exceptionally high torque output allows the KTA50 to turn large-diameter propellers through deep reduction gearing while maintaining efficient propulsion.
Physical & Service Capacities (Marine Versions)
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Engine Weight: 5,166 kg (11,389 lb)
Standard Engine Oil Capacity (varies by sump configuration):
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Sub-base sump: 171–246 L (45–65 gal)
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Deep center sump: 174–204 L (46–54 gal)
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Front or front/center sump: 171–246 L (45–65 gal)
Cooling System Capacity: 197–227 L (52–60 gal)
Large oil and cooling capacities are required to manage the thermal and mechanical loads generated during continuous high-horsepower marine operation.
Marine Configuration Variants
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Mechanical marine KTA50 propulsion engines
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Continuous, prime, and high-output duty ratings
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Single-engine and twin-engine propulsion installations
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Propulsion and auxiliary drive configurations
All marine variants share the same 50-liter V16 architecture, with output differences driven by turbocharging arrangement, calibration, and duty classification.
Typical Marine Transmission Pairings
Due to the extreme torque levels, KTA50 installations require very heavy-duty marine reduction gearing, commonly including:
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Twin Disc MGX-5200 / MGX-5250 series
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ZF Marine 6000 series (ZF 7600 and above)
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Reintjes WAF / WAFI heavy-duty series
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Masson Marine reduction gears for towing and displacement vessels
Transmission selection depends on torque capacity, reduction ratio, shaft diameter, and vessel duty cycle.
Cummins QSK19
Cummins QSK19 – Marine Specifications & Versions
Application: Commercial & Recreational Marine Propulsion
The Cummins QSK19 is a high-output, electronically controlled marine diesel designed for commercial fishing vessels, offshore support vessels, fast ferries, patrol craft, crew boats, tug-assist vessels, and large yachts. In marine service, the QSK19 is selected for applications requiring strong mid-range torque, high cruise power, and dependable operation under sustained load, while maintaining a relatively compact footprint for its power class.
Marine Power Ratings & Torque (QSK19)
Overall Marine Power Range: 500–800 hp
These ratings are offered across multiple marine duty profiles to suit different vessel types and operating cycles:
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Lower-to-mid ratings (500–600 hp):
Common in displacement and semi-displacement hulls prioritizing fuel efficiency and long service life.
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Mid-to-high ratings (600–700 hp):
Widely used in offshore support vessels, patrol craft, and fast commercial boats requiring higher cruise speeds.
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High-output ratings (700–800 hp):
Selected for planing hulls and performance-oriented applications where acceleration and top-end speed are critical.
Peak Torque Range @ 1800 rpm:
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1,978–3,164 Nm (1,459–2,334 ft-lb)
The broad torque band allows the QSK19 to maintain speed efficiently under varying sea states and payload conditions.
Physical & Service Capacities (Marine Versions)
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Engine Weight: 2,189 kg (4,825 lb)
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Standard Engine Oil Capacity: 84.4 liters (89.2 qt)
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Cooling System Capacity: 97 liters (102.5 qt)
The substantial oil and cooling capacities support high thermal loads and extended operating periods typical of commercial marine service.
Marine Configuration Variants
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Electronic marine QSK19 propulsion engines
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Continuous, prime, and high-output duty ratings
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Single-engine and twin-engine propulsion installations
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Propulsion and auxiliary drive configurations
All marine variants share the same 19-liter displacement platform, with output differences driven by turbocharging configuration, engine calibration, and duty rating.
Typical Marine Transmission Pairings
Given the QSK19’s torque output, marine installations typically use heavy-duty marine reduction gears, including:
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Twin Disc MGX-5145 / MGX-5165 series
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ZF Marine 5000 series (ZF 5115, ZF 5250, depending on ratio)
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Reintjes WAF / WAFI series
Transmission selection is based on torque capacity, reduction ratio, shaft size, and vessel duty cycle.
