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QSB6.7/QSB7 for Marine

Available for: Marine, Propulsion Engines, Auxiliary Engines, Recreational Marine, Commercial Marine

Overview

QSB6.7/QSB7 for Marine184-405 kW | 247-542 hp
  • Quiet operation, including an 80-percent reduction in noise at idle, is one of the many benefits from the common-rail fuel system
  • Enhanced sociability from the high-pressure common-rail design virtually eliminates smoke and improves the whole boating experience
  • Maximize vessel performance and access comprehensive vessel diagnostic information via SmartCraft® electronics
  • Peace of mind delivered by the Cummins Captain’s Briefing and global service network
  • Built at Darlington Engine Plant in Darlington, U.K. and Rocky Mount Engine Plant in Rocky Mount, NC, U.S

Specifications

Configuration

In-line, 6-cylinder, 4-stroke diesel

Aspiration

Turbocharged / Aftercooled

Displacement

6.7 L (408 in3)

Bore & Stroke

107 X 124 mm (4.21 X 4.88 in)

Rotation

Counterclockwise facing flywheel

Fuel System

High Pressure Common Rail



Product Dimensions and Weight

Overall Length

mm (in)

1263.8

(49.76)

Length of Block

mm (in)

748.0

(29.45)

Overall Width

mm (in)

910.6

(35.85)

Overall Height

mm (in)

857.0

(33.74)

Weight

kg (lb)

658

(1450)

Dimensions may vary based on selected engine configuration.

             
       
        

Engine Finder Specifications

Markets
Certification Level Tier 3 / Stage IIIA
IMO Tier II
RCD 1
Power 230 - 550 hp / 172 - 410 kW
Torque 720 - 1250 lb-ft / 976 - 1695 N•m

Ratings

Recreational Marine Propulsion Engines (Variable Speed Ratings)

Engine Model

kW

MHP

BHP

Engine Speed (RPM)

Rating Definition

Emissions

QSB6.7

184

250

247

2600

High Output

IMO 2 | EPA 3 | RCD 1

QSB6.7

224

305

301

2600

High Output

IMO 2 | EPA 3 | RCD 1

QSB6.7

261

355

350

2800

High Output

IMO 2 | EPA 3 | RCD 1

QSB6.7

279

380

375

3000

High Output

IMO 2 | EPA 3 | RCD 1

QSB6.7

312

425

419

3000

High Output

IMO 2 | EPA 3 | RCD 1

QSB6.7

353

480

473

3300

High Output

IMO 2 | EPA 3 | RCD 1

QSB6.7

405

550

542

3300

High Output

IMO 2 | EPA 3 | RCD 1

 

Commercial and Government Marine Propulsion Engines (Variable Speed Ratings)

Engine Model

kW

MHP

BHP

Engine Speed (RPM)

Rating Definition

Emissions

QSB6.7

169

230

227

3000

Intermittent

IMO 2 | EPA 3 | EU 3a

QSB6.7

184

250

247

2600

Heavy Duty

IMO 2 | EPA 3 | EU 3a

QSB6.7

224

305

301

2600

Continuous

IMO 2 | EPA 3 | EU 3a

QSB6.7

260

354

349

2800

Intermittent

IMO 2 | EPA 3 | EU 3a

QSB6.7

280

380

375

3000

Intermittent

IMO 2 | EPA 3 | EU 3a

QSB6.7

312

425

419

3000

Intermittent

IMO 2 | EPA 3 | EU 3a

QSB6.7

353

480

473

3000

Intermittent

IMO 2 | EPA 3 | EU 3a

QSB6.7

353

480

473

3300

Government Services

IMO 2 | EPA 3 | EU 3a

QSB6.7

404

550

542

3300

Government Services

IMO 2 | EPA 3 | EU 3a

 

Marine Auxiliary Engines (Fixed Speed Ratings)

Engine Model

kW

MHP

BHP

Engine Speed (RPM)

Rating Definition

Emissions

QSB7-DM

98

134

132

1800 (60 Hz)

Prime Power

EPA 3

QSB7-DM

112

152

150

1800 (60 Hz)

Prime Power

EPA 3

QSB7-DM

122

166

164

1500 (50 Hz)

Prime Power

EPA 3 | EU 3a

QSB7-DM

130

176

174

1800 (60 Hz)

Prime Power

EPA 3

QSB7-DM

142

193

190

1800 (60 Hz)

Prime Power

IMO 2 | EPA 3

QSB7-DM

164

223

220

1500 (50 Hz)

Prime Power

IMO 2 | EPA 3 | EU 3a

QSB7-DM

186

254

250

1800 (60 Hz)

Prime Power

IMO 2 | EPA 3

QSB7-DM

210

286

282

1800 (60 Hz)

Prime Power

IMO 2 | EPA 3


For more information on marine ratings, click here. For more on marine emissions information, click here.

Features

Engine Design – Unmatched performance driven through a perfectly matched turbocharger and a new 24-valve cylinder head that delivers industry-leading power density. Maximize vessel performance and access comprehensive vessel diagnostic information via SmartCraft® electronics. Peace of mind delivered by the Cummins Captain’s Briefing and global service network

 

Fuel System – Bosch HPCR with hardened components to safely operate alternative fuels such as kerosene and JP8/JP5. Quiet operation, including an 80-percent reduction in noise at idle. Enhanced sociability virtually eliminates smoke and improves the whole boating experience.

 

Lubrication System – Front-mounted filters. Oil service interval increased to 500 hours if using ULSD fuels

 

Cooling System – Single loop, low temperature aftercooling eliminates the need for two keel coolers and lowers emissions. Tube and shell heat exchanger designed for superior durability and ease of service with minimal maintenance requirements. Fan drive available for radiator cooled configurations

 

Air Intake System – New Walker air filter significantly reduces noise

 

Exhaust System – Cast water cooled exhaust manifold for lower surface temperatures, safety and improved performance

 

Electrical System – 12v and 24v, isolated and non-isolated, systems available

 

Electronics – 24v Quantum System electronics feature a proven ECM to monitor operating parameters such as fuel consumption, duty cycle, engine load and speed, while providing diagnostics, prognostics and complete engine protection. Simplified electrical customer interface box for all vessel connections to reduce installation complexity

 

Certifications – Complies with U.S. EPA Tier 3 emissions regulations without the use of aftertreatment. Designed to meet the International Association of Classification Societies (IACS) and SOLAS requirements. Consult your local Cummins professional for a complete listing of available class approvals.

 

Optional Equipment Optional Equipment

  • Engine Controls – Digital Throttle and Shift
  • Instrumentation – SmartCraft® digital displays standard with Zeus®, optional as inboard
  • Vessel System Integration – SmartCraft® monitors fluid level, vessel range, depth, vessel speed, rudder position, temperatures and more
  • SL Option Package – a collection of options to reduce engine size and weight. Includes a resized cooling system, side mount filters, low mount turbocharger, disposable closed crankcase air cleaner, remote-manual fuel priming pump, steel oil pan and block mounted engine brackets. Available on the 355, 380 and 425 MHP ratings. Also available a la carte where compatible. 

Brochures Available

Title Bulletin Number Request View  
Commercial And Government Marine Diesel Engines Brochure With Spec Sheet Inserts 4087294 Request View  Download
Cummins Care Marine Flyer 4087307 Request View  Download
Cummins Inboard Joystick Flyer 4087327 Request View  Download
Cummins Zeus Pod Propulsion Sales Sheet 4087291 Request View  Download
Marine Commercial Transport Brochure 4082096 Request View  Download
Marine Offshore Brochure 4082095 Request View  Download
Marine Products Guide 3381946 Request View  Download
QSB6.7 Commercial Marine Spec Sheet 4087433 View  Download
QSB6.7 Marine Propulsion Performance Curve 250 hp @ 2600 RPM EPA Tier 3 Certified QSB6.7 Marine Propulsion Performance Curve 250 hp @ 2600 RPM EPA Tier 3 Certified Request View  Download
QSB6.7 Quantum Series Engine for Recreational Applications Spec Sheet 4087252 Request View  Download
Quantum Series ReCon Engines Flyer 2878914 Request View  Download
Recreational Marine Diesel Engines Brochure With Spec Sheet Inserts 4087293 Request View  Download