Cummins QSB6.7 380HP Marine Diesel Engine

Description

Cummins QSB6.7 380HP Marine Diesel Engine – Product Overview

The Cummins QSB6.7 380HP Marine Diesel Engine is a high-performance marine diesel engine designed for buyers who need dependable propulsion, efficient fuel delivery, and strong power from a proven Cummins platform. With 380 HP output and 6.7 litres of displacement, this engine is suitable for a wide range of marine applications.

Built as an inline 6-cylinder, 4-stroke diesel engine, the QSB6.7 provides smooth operation, strong torque, and practical durability for demanding vessel use. It is suitable for commercial operators, boat owners, marine engineers, boatyards, and repower specialists.

This model features turbocharged and seawater aftercooled aspiration, helping deliver strong power and consistent performance under marine load. It also uses a Bosch high-pressure common rail fuel system, supporting precise fuel delivery and efficient combustion.

The Cummins QSB6.7 380HP Marine Diesel Engine is a strong option for customers comparing Cummins marine engines, 380HP marine diesel engines, QSB6.7 repower engines, inline 6-cylinder marine engines, and EPA Tier 3 certified diesel propulsion systems.

Built for Reliable Marine Propulsion

The Cummins QSB6.7 380HP Marine Diesel Engine is designed for vessels that need dependable power across demanding marine conditions. Its 380 HP output gives compatible boats the strength required for cruising, commercial operation, fishing, patrol work, and repower applications.

Marine diesel engines must deliver consistent power under load, often for long operating periods. The QSB6.7 platform is built around a 6.7L displacement and inline 6-cylinder configuration, giving it a strong foundation for torque and smooth running.

This engine can be suitable for workboats, fishing vessels, patrol craft, commercial boats, cruisers, and selected performance marine applications, depending on vessel size, gearbox selection, cooling setup, and duty cycle.

For buyers replacing an older diesel engine, the QSB6.7 offers modern fuel control, EPA Tier 3 compliance, and flexible electrical options.

Customers can compare this product with related Cummins QSB engines, marine gearboxes, control systems, heat exchanger cooled engines, keel cooled packages, and repower accessories.

6.7L Inline 6-Cylinder Diesel Strength

The Cummins QSB6.7 380HP Marine Diesel Engine uses an inline 6-cylinder, 4-stroke diesel configuration with 6.7 litres of displacement. This layout supports smooth power delivery, strong torque, and dependable performance in marine propulsion applications.

Inline 6-cylinder marine engines are valued for their balance, smoothness, and load-carrying strength. These qualities are important for boats that need to maintain cruising speed, handle changing sea conditions, and carry passengers, fuel, cargo, or equipment.

The 4-stroke diesel design helps provide efficient combustion and long-term durability when correctly installed and maintained.

With 380 HP, this engine sits in a practical power range for serious recreational and commercial vessels. It gives buyers a strong diesel option without moving into much larger displacement classes.

For customers seeking a Cummins 6.7L marine diesel engine, the QSB6.7 offers proven inline-six strength and practical marine capability.

Turbocharged and Seawater Aftercooled Performance

The Cummins QSB6.7 380HP Marine Diesel Engine is turbocharged and seawater aftercooled, helping it deliver strong horsepower and consistent performance under load.

Turbocharging increases airflow into the engine, allowing the 6.7L diesel platform to produce more power and torque. This helps improve acceleration, load handling, and cruising capability.

Seawater aftercooling helps reduce the temperature of compressed intake air after turbocharging. Cooler intake air can support more efficient combustion and stronger performance, especially during sustained marine operation.

This combination is important for vessels that need dependable power in real-world conditions, including heavy loads, long cruises, commercial work, and changing sea states.

For buyers comparing turbocharged marine diesel engines, the Cummins QSB6.7 provides a strong balance of output, efficiency, and marine-focused cooling support.

Bosch High-Pressure Common Rail Fuel System

The Cummins QSB6.7 380HP Marine Diesel Engine uses a Bosch high-pressure common rail fuel system. This is one of the strongest technical features for buyers who value fuel efficiency, smoother running, and controlled performance.

High-pressure common rail fuel injection helps deliver fuel with precision. This supports better combustion, improved throttle response, lower smoke, and more efficient fuel use compared with older mechanical injection designs.

For marine operators, fuel efficiency affects range, operating cost, refueling frequency, and overall vessel productivity. A modern common rail system can help improve the engine’s operating economy while still delivering strong power.

The system also supports smoother and more refined engine behavior, which matters for recreational vessels, passenger applications, and commercial operators who spend long hours on the water.

For customers looking for a Cummins common rail marine diesel engine, the QSB6.7 is a strong modern option.

Heat Exchanger Cooling With Keel Cooling Option

The Cummins QSB6.7 380HP Marine Diesel Engine is listed with heat exchanger cooling, with keel cooling optional. This gives buyers flexibility based on vessel type, operating environment, and installation requirements.

Heat exchanger cooling is commonly used in marine diesel installations. It helps regulate engine temperature using a closed coolant circuit while transferring heat through a marine heat exchanger.

Keel cooling can be useful for workboats, commercial vessels, inland boats, and special-duty applications where external cooling through a keel cooler is preferred.

Choosing the correct cooling system is important for engine protection, installation planning, maintenance access, and long-term reliability.

Buyers should confirm whether heat exchanger cooling or keel cooling is best for their vessel before ordering, especially for commercial use or repower projects.

EPA Tier 3 Marine Certified

The Cummins QSB6.7 380HP Marine Diesel Engine is listed as EPA Tier 3 marine certified. This makes it a strong choice for buyers who need recognized emissions compliance for marine applications.

EPA Tier 3 certification is important for many new installations, repowers, commercial vessels, and regulated operating environments. It helps confirm that the engine meets applicable emissions requirements for its category.

The engine’s common rail fuel system, turbocharging, and electronic fuel control support cleaner and more efficient operation.

Buyers should confirm final certification documents, engine serial details, and regional compliance requirements before purchase.

For customers who need a compliant 380HP marine diesel engine, the Cummins QSB6.7 offers a professional specification with recognized emissions certification.

12V or 24V Electrical Options

The Cummins QSB6.7 380HP Marine Diesel Engine is available with 12V or 24V electrical options, giving buyers flexibility for different vessel electrical systems.

Electrical compatibility is important in marine installations because the engine must integrate with the vessel’s starting system, controls, charging setup, alarms, instrumentation, and onboard electrical architecture.

A 12V setup is common on many recreational vessels, while 24V systems are often used on larger boats, commercial vessels, and heavier-duty marine applications.

Buyers should confirm the correct electrical configuration before purchase to match the vessel’s existing system and installation plan.

For repower projects, choosing the right electrical option can reduce installation complexity and help avoid compatibility issues.

Rotation and Installation Considerations

The Cummins QSB6.7 380HP Marine Diesel Engine is listed with counterclockwise rotation when facing the flywheel. This technical detail is important for marine drivetrain planning.

Engine rotation can affect gearbox selection, shaftline compatibility, propeller direction, and overall installation design. Buyers should confirm rotation requirements with a marine engineer or installer before purchase.

This is especially important for repower projects where the new engine must match or properly integrate with existing drivetrain components.

The engine should also be matched with the correct gearbox ratio, mounts, exhaust setup, cooling layout, controls, propeller, and service access.

For buyers planning a professional installation, confirming rotation and drivetrain compatibility early helps avoid costly fitting problems.

Why the Cummins QSB6.7 380HP Is a Smart Choice

The Cummins QSB6.7 380HP Marine Diesel Engine stands out because it combines 380 HP output, 6.7L inline-six diesel strength, turbocharged and seawater aftercooled performance, Bosch high-pressure common rail fuel injection, EPA Tier 3 marine certification, and flexible 12V or 24V electrical options.

Many buyers in this category need a dependable marine diesel engine that can support serious vessel operation without excessive complexity. The QSB6.7 offers a strong balance of power, efficiency, durability, and compliance.

The common rail fuel system supports efficient fuel delivery and smoother performance. The heat exchanger cooling system provides practical marine temperature control, while optional keel cooling gives flexibility for certain vessel types.

For customers searching for a Cummins QSB6.7 380HP marine diesel engine, this model is a strong choice for repower projects, commercial use, and dependable inboard propulsion.

Who Should Choose This Marine Diesel Engine

The Cummins QSB6.7 380HP Marine Diesel Engine is best for boat owners, commercial operators, marine engineers, shipyards, and repower specialists who need strong and efficient diesel propulsion.

It is suitable for cruisers, workboats, patrol craft, fishing boats, commercial vessels, and selected performance marine applications requiring 380 HP diesel power.

This model is especially useful for buyers who value Bosch high-pressure common rail fuel injection, turbocharged performance, seawater aftercooling, EPA Tier 3 compliance, heat exchanger cooling, and 12V or 24V electrical flexibility.

Buyers who need a different horsepower rating, exact gearbox package, mounting arrangement, control system, keel cooling configuration, or installation dimensions should confirm the full engine package before purchase.

Technical Specifications

Key Product Details and Specifications

The Cummins QSB6.7 380HP Marine Diesel Engine delivers 380 HP from a 6.7L inline 6-cylinder, 4-stroke diesel platform.

It uses turbocharged and seawater aftercooled aspiration, helping the engine deliver strong marine performance under load.

The Bosch high-pressure common rail fuel system supports precise fuel injection, efficient combustion, smoother running, and improved operating economy.

The engine is heat exchanger cooled, with keel cooling optional for vessels that require a different cooling arrangement.

This model is listed as EPA Tier 3 marine certified, making it suitable for buyers who need recognized emissions compliance.

Electrical options include 12V or 24V systems, giving flexibility for different vessel setups.

Rotation is listed as counterclockwise when facing the flywheel, which should be confirmed during gearbox and drivetrain planning.

Buy With Confidence

When buying the Cummins QSB6.7 380HP Marine Diesel Engine, customers should confirm vessel type, power requirement, duty cycle, engine room space, cooling configuration, gearbox compatibility, electrical voltage, rotation, controls, propeller matching, emissions documentation, and installation planning.

This model is a strong choice for buyers who need a Cummins QSB6.7 marine diesel engine with 380 HP output, 6.7L inline-six power, Bosch high-pressure common rail fuel injection, turbocharged and seawater aftercooled performance, and EPA Tier 3 certification.

Customers can compare this product with related Cummins QSB engines, 380HP marine diesel engines, heat exchanger cooled packages, keel cooled options, marine gearboxes, engine controls, and repower components.

Professional guidance is recommended for marine diesel installation and repower projects. Correct engine sizing, gearbox selection, cooling setup, mount alignment, exhaust routing, electrical integration, shaftline planning, and service access help support safer operation, better efficiency, and long-term reliability.

Frequently Asked Questions

What is the Cummins QSB6.7 380HP Marine Diesel Engine best used for?

The Cummins QSB6.7 380HP Marine Diesel Engine is best used for cruisers, fishing boats, workboats, patrol craft, commercial vessels, and repower projects requiring dependable 380 HP diesel propulsion.

How much power does the Cummins QSB6.7 produce?

This model produces 380 HP, making it suitable for vessels that need strong inline-six marine diesel performance.

What type of engine is the Cummins QSB6.7?

The Cummins QSB6.7 is an inline 6-cylinder, 4-stroke diesel engine with 6.7 litres of displacement.

What fuel system does this engine use?

The engine uses a Bosch high-pressure common rail fuel system, which supports precise fuel injection, efficient combustion, and smoother operation.

Is the Cummins QSB6.7 380HP EPA certified?

Yes, this model is listed as EPA Tier 3 marine certified. Buyers should confirm final documentation for their vessel and region.

What cooling system does this engine use?

The engine is listed as heat exchanger cooled, with keel cooling optional. Buyers should confirm the correct cooling setup for their vessel before ordering.

What electrical options are available?

The Cummins QSB6.7 380HP Marine Diesel Engine is available with 12V or 24V electrical options, allowing buyers to match the engine to the vessel’s electrical system.