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QSB6.7/QSB7 for 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)

Model

kW

MHP

BHP

Speed (RPM)

Rating

Emissions

Performance Curve

QSB6.7

184

250

247

2600

High Output

IMO 2 | EPA 3 | RCD 2

FR93858

QSB6.7

224

305

301

2600

High Output

IMO 2 | EPA 3 | RCD 2

FR93859

QSB6.7

261

355

350

3000

High Output

IMO 2 | EPA 3 | RCD 2

FR94133

QSB6.7 SL

261

355

350

3000

High Output

IMO 2 | EPA 3 | RCD 2

FR94979

QSB6.7

279

380

375

3000

High Output

IMO 2 | EPA 3 | RCD 2

FR94131

QSB6.7 SL

279

380

375

3000

High Output

IMO 2 | EPA 3 | RCD 2

FR94978

QSB6.7

312

425

419

3000

High Output

IMO 2 | EPA 3 | RCD 2

FR94129

QSB6.7 SL

312

425

419

3000

High Output

IMO 2 | EPA 3 | RCD 2

FR94977

QSB6.7

353

480

473

3300

High Output

IMO 2 | EPA 3 | RCD 2

FR94127

QSB6.7

405

550

542

3300

High Output

IMO 2 | EPA 3 | RCD 2

FR94125

 

Commercial and Government Marine Propulsion Engines (Variable Speed Ratings)

Model

kW

MHP

BHP

Speed (RPM)

Rating

Emissions

FR

QSB6.7-SW

169

230

227

3000

Intermittent

IMO 2 | EPA 3 | EU 3a

FR94135

QSB6.7-SW

184

250

247

2600

Heavy Duty

IMO 2 | EPA 3 | EU 3a

FR93960

QSB6.7-KC

184

250

247

2600

Heavy Duty

IMO 2 | EPA 3 | EU 3a

FR93962

QSB6.7-SW

224

305

301

2600

Medium Continuous

IMO 2 | EPA 3 | EU 3a

FR93961

QSB6.7-KC

224

305

301

2600

Medium Continuous

IMO 2 | EPA 3 | EU 3a

FR93963

QSB6.7-SW

261

355

350

2800

Intermittent

IMO 2 | EPA 3 | EU 3a

FR94375

QSB6.7-KC

261

355

350

3000

Intermittent

IMO 2 | EPA 3 | EU 3a

FR95083

QSB6.7-SW

280

380

375

3000

Intermittent

IMO 2 | EPA 3 | EU 3a

FR94132

QSB6.7-SW

312

425

419

3000

Intermittent

IMO 2 | EPA 3 | EU 3a

FR94130

QSB6.7-KC

312

425

419

3000

Intermittent

IMO 2 | EPA 3 | EU 3a

FR95081

QSB6.7-SW

353

480

473

3000

Intermittent

IMO 2 | EPA 3 | EU 3a

FR95035

QSB6.7-SW

353

480

473

3300

Government Services

IMO 2 | EPA 3 | EU 3a

FR94128

QSB6.7-SW

404

550

542

3300

Government Services

IMO 2 | EPA 3 | EU 3a

FR94126

 

Marine Auxiliary Engines (Fixed Speed Ratings)

Model

kW

MHP

BHP

Speed (RPM)

Rating

Emissions

FR

QSB7-DM

98

134

132

1800 (60 Hz)

Prime Power

IMO 2 | EPA 3

FR93773

QSB7-DM

112

152

150

1800 (60 Hz)

Prime Power

IMO 2 | EPA 3

FR93772

QSB7-DM

122

166

164

1500 (50 Hz)

Prime Power

IMO 2 | EPA 3 | EU 3a

FR93775

QSB7-DM

130

176

174

1800 (60 Hz)

Prime Power

IMO 2 | EPA 3

FR93776

QSB7-DM

142

193

190

1800 (60 Hz)

Prime Power

IMO 2 | EPA 3

FR93771

QSB7-DM

164

223

220

1500 (50 Hz)

Prime Power

IMO 2 | EPA 3 | EU 3a

FR93774

QSB7-DM

186

254

250

1800 (60 Hz)

Prime Power

IMO 2 | EPA 3

FR93766

QSB7-DM

210

286

282

1800 (60 Hz)

Prime Power

IMO 2 | EPA 3

FR93215


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

  • 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  
2017 Marine Products Guide 3381946 Request View  Download
C Command Electronic Information System Brochure 4082006 Request View  Download
Commercial And Government Marine Diesel Engines Brochure With Spec Sheet Inserts 4087294 Request View  Download
Cummins Care Marine Flyer 4087307 Request View  Download
Marine Defense Brochure 4087453 Request View  Download
Marine Maintenance Schedule Flyer 5410779 View  Download
Marine Warranty Overview Flyer 5410780 View  Download
QSB6.7 Commercial Marine Spec Sheet 4087433 View  Download
QSB6.7 Quantum Series Engine for Recreational Applications Spec Sheet 4087252 Request View  Download
QSB6.7 Quantum Series Engine for Recreational Applications Spec Sheet - A4 format 4087455 View  Download

Technical Documents Available

Title Bulletin Number View  
C Command HD Elite Plus Wiring Diagram 5272052 View  Download
C Command HD Wiring Diagram 5262653 View  Download
DTS (SmartCraft 2.2) System Architecture & Option Overview Diagram 4082046 View  Download
DTS (SmartCraft 2.2) Wiring Diagram 4082050 View  Download
Non-DTS (SmartCraft 2.2) System Architecture & Option Overview Diagram 4082047 View  Download
Preliminary Non-DTS (SmartCraft 2.2) Wiring Diagram 4082051 View  Download
QSB6.7 HO Marine Performance Curve 224 kW (305 hp) @ 2600 RPM (EPA Tier 3) M-93959 View  Download
QSB6.7 Marine Engine General Datasheet D31-MX-1 View  Download
QSB6.7 Marine Propulsion 355-550 hp Installation Drawing 4954063 View  Download
QSB6.7 Propulsion 230-305 hp Marine Installation Drawing 4954074 View  Download
QSB6.7 w/ Zeus Drive Marine Installation Drawing 4954000 View  Download
QSB6.7 w/ Zeus Drive Marine Installation Drawing 4954001 View  Download
QSB6.7 w/ Zeus Drive Marine Installation Drawing 4954002 View  Download
QSB6.7 w/ Zeus Drive Marine Installation Drawing 4954003 View  Download
QSB6.7 w/ Zeus Drive Marine Installation Drawing 4954004 View  Download
QSB6.7 w/ ZF85A Marine Installation Drawing 4953999 View  Download
QSB6.7 w/ ZF85IV Marine Installation Drawing 4953998 View  Download
QSB6.7/QSB7 Subsystem Marine Installation Drawing 4953945 View  Download
SmartCraft 1.0 System Architecture & Option Overview Diagram 4082056 View  Download
SmartCraft 2.5 DTS Marine Propulsion Wiring Diagram 4304664 View  Download
SmartCraft 2.5 Non-DTS Marine Propulsion Wiring Diagram 4304665-03 View  Download
SmartCraft 2.5 w/ Zeus Marine Propulsion Wiring Diagram 4304663 View  Download
Zeus (SmartCraft 2.1) System Architecture & Option Overview Diagram 4082043 View  Download
Zeus (SmartCraft 2.1) Wiring Diagram 4082045 View  Download
Zeus Helm Components Installation Drawing 4953822 View  Download