Specification	Detail
Engine Type	4-cylinder, inline, 4-stroke diesel
Displacement	4.5 liters (275 cubic inches)
Bore x Stroke	4.02 in x 4.88 in (102 mm x 124 mm)
Aspiration	Turbocharged and Aftercooled
Fuel System	High-Pressure Common Rail (HPCR) with ECM
Valvetrain	OHV, 4 valves per cylinder
Compression Ratio	17.3:1
Power Output	130–210 HP @ 2,600–2,800 RPM
Peak Torque	400–520 lb-ft @ 1,600 RPM
Cooling System	Liquid-cooled with belt-driven water pump
Lubrication Capacity	Approx. 11 quarts (10.5 liters)
Dry Weight	~775–850 lbs (352–386 kg)
Emissions Certification	EPA Tier 3 / Tier 4 Final, Euro Stage IV–V
Engine Control	Full-authority ECM with CAN-bus communication

The ISB 4.5 combines the durability of cast-iron block and head design with the sophistication of electronic fuel management. Its compact architecture allows easy installation in tight engine bays while still delivering the torque needed for demanding mechanical loads.

Cummins ISB 5.9 Engine Specifications

Specification	Detail
Configuration	Inline 6-cylinder, 4-stroke diesel
Displacement	5.9 liters (359 cubic inches)
Bore x Stroke	4.02 in x 4.72 in (102 mm x 120 mm)
Aspiration	Turbocharged and Aftercooled
Fuel System	High-Pressure Common Rail (HPCR) / Bosch VP44
Compression Ratio	17.2:1
Horsepower Range	175–325 HP @ 2,500–2,900 RPM
Peak Torque	460–600 lb-ft @ 1,400–1,600 RPM
Cooling System	Liquid-cooled with belt-driven water pump
Lubrication Capacity	15–17 quarts (14–16 liters)
Dry Weight	~1,100 lbs (499 kg)
Emissions Certification	Tier 2 / Tier 3 (depending on model year)
Valvetrain	OHV, 4 valves per cylinder
ECM	Full-authority, CAN-bus capable

The ISB 5.9 engine maintained many design features of the original 6BT—such as its gear-driven camshaft and forged-steel crankshaft—but introduced electronic controls and higher fuel injection pressures, improving both efficiency and emissions performance. Many versions also included an exhaust gas recirculation (EGR) system to comply with U.S. EPA regulations.

Cummins ISB 6.7 Engine Specifications

Specification	Detail
Configuration	Inline 6-cylinder, 4-stroke diesel
Displacement	6.7 liters (408 cubic inches)
Bore x Stroke	4.21 in x 4.88 in (107 mm x 124 mm)
Aspiration	Turbocharged and Aftercooled, VGT
Fuel System	High-Pressure Common Rail (HPCR)
Compression Ratio	17.3:1
Horsepower Range	200–360 HP @ 2,500–2,800 RPM
Peak Torque	520–800 lb-ft @ 1,400–1,800 RPM
Emissions Tier	Tier 3, Tier 4 Final, Euro Stage IV/V
Cooling System	Liquid-cooled with belt-driven water pump
Oil Capacity	16–18 quarts (15–17 liters)
Dry Weight	~1,150 lbs (521 kg)
Engine Management	ECM with CAN bus, diagnostic logging

The ISB 6.7 combines the strength of a cast-iron block and head with modern electronics and emissions technology. Its VGT allows for variable boost levels based on load demand, improving both throttle response and exhaust aftertreatment performance.

About the Cummins QSB 4.5 Engine

Versatile. Durable. Proven in the Field.

The QSB 4.5 engine is a turbocharged, aftercooled, four-cylinder diesel engine with a high-pressure common rail (HPCR) fuel system. It is based on the B Series platform and designed to meet rigorous Tier 3 and Tier 4 Final emissions standards without sacrificing performance.

Core features include:

Displacement: 4.5 liters
Configuration: 4-cylinder inline
Valvetrain: 4 valves per cylinder
Fuel System: HPCR with electronic control
Emissions: EGR, DOC, and/or SCR systems (varies by version)
Power Output: 110–173 HP depending on application

The QSB 4.5 is built for long hours and hard work, and is supported by Cummins’ extensive service history and component interchangeability with other B Series models.

About the Cummins QSB 5.9 Marine Engine

Built for Power, Efficiency, and Quiet Operation

The QSB 5.9 is a 5.9-liter, 6-cylinder diesel engine with high-pressure common rail fuel injection. It’s engineered specifically for marine applications, with enhanced corrosion protection, a fresh water cooling system, and emission compliance technologies designed for low-speed continuous operation.

Core features:

HPCR Fuel System – For clean combustion and responsive acceleration
24-Valve Configuration – Optimized air/fuel mixing for smoother performance
Turbocharged and Aftercooled – Keeps temperatures controlled under load
Tier 2 / Tier 3 Compliant – Meets global marine emissions requirements
Low Noise Profile – Integrated sound-dampening and reduced vibration

This engine is commonly used in yachts, trawlers, sport boats, pilot vessels, fishing boats, and onboard power systems.

About the Cummins QSB 6.7 Engine

Quiet, Powerful, and Built for Marine Demands

The Cummins QSB 6.7 is a 6-cylinder, 6.7-liter marine engine designed to deliver smooth performance even in demanding marine environments. It uses High-Pressure Common Rail (HPCR) fuel injection, electronic control systems, and a full-authority ECM to maximize power, reduce noise, and meet global emissions standards.

Key features include:

80% idle noise reduction for a quieter boating experience
Tier 2 and Tier 3 emissions compliance
Advanced turbocharging and aftercooling
Low vibration and marine-specific mounting systems
Compact footprint ideal for tight engine compartments

This engine is commonly used in patrol boats, ferries, workboats, pleasure yachts, and onboard generators.

Marine Applications for the Cummins QSB 6.7 Engine

The QSB 6.7’s robust design and flexible power output make it ideal for a range of vessel types and marine systems. Common applications include:

Commercial Vessels

Passenger ferries
Pilot boats
Workboats and harbor tugs
Coastal and inshore fishing vessels

Recreational Boats

Yachts and cruisers
Sportfishing boats
Sailing vessels with auxiliary engines

Auxiliary Power Systems

Marine generators
Hydraulic pump systems
Winch and bow thruster drives

The QSB 6.7 is trusted worldwide for its ability to combine power and efficiency in

Cummins QSB 7 Marine Engine Parts

The Cummins QSB 7 engine is a powerful, emissions-compliant marine diesel engine designed for exceptional durability and smooth, quiet operation. Whether you operate a workboat, yacht, or auxiliary power system, the QSB 7 is built to meet the demands of commercial and recreational use. At Diesel Pro Power, we offer a full line of Cummins QSB 7 parts—shipped globally within 24 hours and supported by expert service.

About the Cummins QSB 7 Engine

Power and Reliability on the Water

The Cummins QSB 7 is a 6-cylinder, 6.7-liter engine (often referred to as 7.0L-class due to advanced upgrades) designed for marine propulsion and onboard power. Featuring a high-pressure common rail fuel system, full-authority ECM, and a robust cooling architecture, it’s one of the most advanced options in Cummins’ midrange marine portfolio.

Key features include:

Quiet operation and low vibration
Integrated diagnostics and fuel mapping via ECM
EPA Tier 3 and IMO-compliant emissions systems
Turbocharged and aftercooled
Optimized for high-load marine conditions

The QSB 7 balances efficient fuel use with high torque output, making it ideal for propulsion or auxiliary duty in a variety of vessels.

Marine Applications for the Cummins QSB 7 Engine

The Cummins QSB 7’s durability and quiet profile make it suitable for both heavy-duty commercial applications and refined recreational settings.

Common Vessel Types

Pilot boats and patrol craft
Passenger ferries and water taxis
Luxury yachts and trawlers
Commercial fishing vessels
Harbor workboats and support vessels

Auxiliary Systems

Onboard marine generators
Bow thruster power units
Hydraulic pump drive systems
Firefighting and emergency pump sets

Its flexible mounting options and compact size make it ideal for engine room retrofits and new vessel designs alike.

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Cummins ISB 4.5 Engine Specifications