Cummins 6B Engine Parts

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Parts for Cummins 6B Engines

Premium Cummins 6B Marine and Industrial Engine Parts from Diesel Pro Power

The Cummins 6B engine—also referred to as the 6BT—is a workhorse in the world of diesel power. With a 5.9L inline-six configuration, mechanical fuel injection, and robust construction, it has been widely adopted in marine propulsion systems, industrial generators, irrigation setups, and hydraulic drive applications. But to maintain the legendary reliability and performance Cummins engines are known for, only the right parts will do.

At Diesel Pro Power, we’re proud to offer a full range of high-quality, marine-grade and industrial-spec Cummins 6B parts, ready to ship worldwide in just 24 hours. Whether you’re rebuilding an engine or replacing a worn-out water pump on your vessel or stationary unit, we deliver fast, trusted service and expert support.

We serve professional operators, marine technicians, industrial maintenance teams, shipyards, and government agencies with fast, global delivery and personalized customer care. From top-end kits to precision fuel parts, Diesel Pro Power is your one-stop shop for Cummins 6B parts.

Buy Cummins 6B Parts Online – Accurate, Fast & Global

Shop a Complete Selection of 6B Engine Parts

We carry one of the most complete inventories of Cummins 6B parts available online, with every component selected to withstand the demands of continuous-duty marine and industrial applications. All parts are vetted for compatibility with 6B, 6BT, and 6BTA mechanical configurations.

Fresh Water Pumps for Cummins 6B

Our fresh water pumps are engineered to circulate coolant through closed-loop marine or industrial systems such as heat exchangers or keel coolers. These pumps are ideal for 6B engines operating in:

Marine propulsion systems
Gensets onboard commercial vessels
Hydraulic power units with closed cooling loops

Features:

Heavy-duty cast iron housings
Sealed bearings for longer service life
Compatibility with standard fan belts
Optional pulley kits and belt tensioners
Covered by a one-year warranty

We also carry related accessories such as:

Silicone coolant hoses
Thermostat assemblies
Expansion tank fittings and gaskets

Sea Water Pumps for Cummins 6B

Diesel Pro Power supplies raw water (sea water) pumps specifically designed for marine Cummins 6B installations. These pumps play a critical role in drawing in seawater to cool engine components or heat exchangers.

Key features:

Bronze marine-grade construction
Long-life impellers and wear-resistant seals
Bolt-on installation with optional bracket kits

You’ll also find:

Pump repair kits
Impellers
Zinc anodes
Raw water strainers
Gaskets and mounting bolts

These pumps are essential in protecting your engine from overheating and are recommended for preventative replacement every season in saltwater environments.

Connecting Rods for Cummins 6B

Our connecting rod assemblies are available in matched sets and include:

Lower and upper rod bearings
Standard and oversize options
High-load ratings for continuous-duty operation

These components are crucial for maintaining smooth piston travel and preventing engine knock or bearing failure—especially under high-torque conditions found in marine propulsion or industrial applications like pumps and compressors.

Cylinder Heads for Cummins 6B

We offer fully assembled cylinder heads for Cummins 6B engines, featuring:

New valves, valve springs, guides, and seals
Precision-machined injector tubes
Pressure testing for leak-free performance

Accessories include:

Cylinder head bolts
Push rods
Rocker arm assemblies
Valve cover gaskets

Ideal for rebuilds following head warpage, overheating, or excessive blow-by, our 6B heads are designed to drop in and restore factory compression and performance.

Engine Overhaul Kits for Cummins 6B

Whether you're planning scheduled maintenance or recovering from a failure, our 6B engine rebuild kits offer a complete solution. These kits include:

Pistons and piston rings
Main and rod bearings
Upper and lower gasket sets
Valve train seals
Oil seals
Thrust washers

We stock standard and oversize kits to accommodate cylinder wear or journal polishing. Rebuild kits are packaged for:

Marine 6B propulsion engines
Industrial 6B generators
Hydraulic power units or pump engines

Fuel System Components for Cummins 6B

Fuel delivery must be precise for optimal performance. Our 6B fuel system parts include:

Mechanical fuel injectors
Injector nozzles and seals
Injection pumps
Fuel lift pumps
Fuel filter heads and spin-on filters
Injector return lines

Each injector and pump is built to OEM specs, with marine fuel blend compatibility and corrosion resistance. Proper injector maintenance prevents power loss, white smoke, or uneven combustion.

Oil System Components for Cummins 6B

Oil circulation is vital for engine longevity. We carry full oil system support for 6B Cummins, including:

Oil filters and filter bases
Oil coolers and seals
Oil pressure switches and sensors
Oil pumps and pickup assemblies
Drain plugs and pan gaskets

Built for extended-duty schedules and extreme operating temperatures, these components ensure proper lubrication of internal parts and protect against premature wear.

Starters, Alternators, and Electrical Components for Cummins 6B

Diesel Pro Power supplies:

12V and 24V starters
Marine-grade alternators
Glow plug and pre-heat systems (for cold weather)
Engine sensors: temperature, RPM, oil pressure
Wiring harnesses and relay panels

All electrical components are waterproof and vibration-tested for marine use. Need a specific solenoid or bracket? We have you covered.

Additional Cummins 6B Parts We Offer

We also stock:

Engine mounts and vibration isolators
Gasket kits (top, bottom, and full sets)
Thermostats and temperature switches
Marine control cables
Exhaust elbows and risers
Belt kits and pulleys
Air filters and intake manifolds
Turbochargers and related hardware (for 6BTA variants)

Why Buy Your 6B Cummins Parts From Diesel Pro Power?

Global Reach with Local-Level Service

We support diesel professionals and operators around the world with parts that ship out within 24 hours. Our warehouse stocks thousands of parts ready for same-day fulfillment.

15,000+ Satisfied Customers

With decades in business and thousands of global customers—from commercial fishing fleets to remote mining camps—we’ve built trust through reliable service, fast shipping, and helpful guidance.

Secure and Simple Ordering

User-friendly website with accurate parts search
Secure payment portal with encryption
Prepaid duty and tax options for international buyers
Multilingual customer service available

Unmatched Technical Support

Need help selecting the correct piston oversize? Unsure whether a marine head gasket is thicker than industrial? Our team of diesel experts can guide you based on your engine serial number or CPL.

Cummins 6B Applications: Built for Work, Not Commute

The 6B is a preferred powerplant in a variety of heavy-duty scenarios:

Marine Applications

Commercial fishing vessels
Towboats and tugboats
Pilot boats and patrol craft
Onboard auxiliary gensets
Bilge, fire, and hydraulic pumps

Industrial Applications

Power generation sets for hospitals, data centers, and plants
Irrigation and water pumping stations
Compressor systems for mining and manufacturing
Concrete mixing plants and sawmill engines
Hydraulic drive systems for cranes and presses

These environments demand engines that run for hours or days on end—and the Cummins 6B delivers.

Maintenance Tips for Marine and Industrial Cummins 6B Engines

Marine Preventative Maintenance

Replace seawater impellers every 100 hours or annually
Inspect zinc anodes quarterly and replace if 50% degraded
Flush heat exchangers regularly to remove scaling
Check coolant PH and use marine-approved antifreeze
Grease marine throttle and shift cables

Industrial Maintenance Routine

Replace oil and fuel filters every 250–300 hours
Clean air filters regularly in dusty sites
Inspect belts and coolant hoses monthly
Keep detailed logbooks of run time
Test coolant and oil pressure sensors every 500 hours

Recommended Replacement Intervals

Component	Marine Use	Industrial Use
Oil Filter	Every 150–200 hours	Every 250 hours
Fuel Filter	Every 100–150 hours	Every 200 hours
Raw Water Impeller	Every 100 hours or annually	N/A
Zinc Anodes	Every 3–6 months	N/A
Thermostat	Every 2 years	Every 2 years
Cylinder Head	As needed (overheating)	As needed
Injectors	Every 3,000 hours	Every 4,000 hours
Belts	Every 2 years	Every 2 years
Fresh Water Pump	Every 2–3 years	Every 3–4 years

Order Cummins 6B Parts Online or Call Our Experts Today

Place your order today and receive:

Worldwide shipping within 24 hours
OEM-quality parts at competitive prices
Expert technical guidance for every order

Contact Diesel Pro Power

Phone (US & Canada): 1-888-433-4735
International: +1-305-545-5588
Hours: Monday–Friday, 8 AM–5 PM EST
Email: Contact us via our website with your engine details

Whether you’re running a portside generator or refitting a commercial vessel, we’ll make sure you get the right parts, fast.

Engine Specifications & Applications of the Cummins 6B Engine

Overview of the Cummins 6B Engine

The Cummins 6B is a naturally aspirated, inline six-cylinder diesel engine that laid the foundation for one of the most respected engine platforms in industrial and marine applications. As the predecessor to the better-known 6BT and 6BTA engines, the 6B is a simplified, turbo-free version of the 5.9L B Series platform, ideal for low-maintenance, continuous-duty roles. With no turbocharger or intercooler, the 6B engine emphasizes simplicity, reliability, and steady torque delivery, making it especially attractive to users who require maximum uptime in demanding environments.

First introduced in the early 1980s, the 6B has seen long-standing service in power generation, marine support systems, agricultural equipment, construction platforms, and oilfield utility machinery. Its mechanical injection system and lack of electronic components make it ideal for remote installations, export applications, and non-emissions markets.

Cummins 6B 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	Naturally Aspirated
Fuel System	Mechanical direct injection (Bosch rotary or inline pump)
Compression Ratio	17.5:1
Horsepower Range	80–120 HP @ 2,500–2,800 RPM
Peak Torque	230–320 lb-ft @ 1,600–1,800 RPM
Cooling System	Liquid-cooled with belt- or gear-driven water pump
Oil Capacity	15–16 quarts (14–15 liters)
Dry Weight	950–1,050 lbs (431–476 kg)
Flywheel Housing	SAE #2 or #3
Emissions Tier	Pre-Tier 1 (Non-Electronic)
Valvetrain	OHV (Overhead Valve) with 2 valves per cylinder
Service Life (Rebuild)	10,000–15,000+ hours with proper maintenance

The 6B was engineered to withstand harsh operating conditions while maintaining low operating costs. With fewer moving parts than turbocharged variants, the 6B delivers consistent performance and ease of servicing, making it ideal for remote locations and legacy equipment operators.

Common Applications of the Cummins 6B Engine

Due to its balance of power, mechanical simplicity, and rugged construction, the Cummins 6B is used in a wide range of applications. It particularly excels in steady-state or low-RPM operations, where load predictability and uptime are critical. From backup generators to agricultural irrigation engines, the 6B provides reliable performance with minimal complexity.

1. Marine Auxiliary and Generator Applications

Although the 6B is not commonly used for primary marine propulsion, it is a proven performer in auxiliary systemsaboard commercial and work vessels. Its smooth torque curve and naturally aspirated design make it a preferred power source for systems that require long-duration runtime with low maintenance needs.

Marine Applications Include:

Onboard diesel generator sets (40–80 kW range)
Fire pump engines
Desalination pump drives
Hydraulic system support (winches, cranes)
Refrigeration compressor engines
Fuel transfer and bilge pumping systems

With no turbocharger or intercooler, the 6B handles marine engine room conditions well—less heat, fewer components to fail, and lower risk of performance degradation due to salt or humidity exposure.

2. Industrial and Commercial Generator Systems

In the world of stationary power generation, the Cummins 6B is a workhorse. Whether used as a backup system or a prime power engine, it is appreciated for fuel economy, mechanical reliability, and consistent performance at fixed RPMs.

Generator Use Cases:

Remote-site generators (construction camps, farms, rural homes)
Emergency backup gensets (commercial or industrial buildings)
Continuous duty power for communication towers
Utility and grid-tied standby power plants
Mobile generator trailers and skids

Operators prefer the 6B for its ease of starting, simplicity of integration, and long overhaul intervals—especially in settings where electronic controls would be a liability.

3. Agricultural Equipment

The Cummins 6B is highly suitable for use in farm and irrigation systems, especially in parts of the world where Tier 4 compliance is not required. Its six-cylinder design offers a balance of smooth operation and steady torque ideal for rotational or pumping duties.

Agricultural Use Cases:

Diesel-powered irrigation systems
Grain augers and dryers
Skid-mounted pumps
Feed mixers and milling equipment
Repower engines for older tractors and combines

Its naturally aspirated airflow makes the 6B well suited for environments with high dust or particulate matter, reducing maintenance compared to turbocharged models.

4. Construction & Material Handling Equipment

Though more commonly replaced by newer 6BT and 6BTA variants, the 6B still powers many legacy construction and utility machines around the world.

Equipment Examples:

Wheel loaders and small dozers
Aerial work platforms and boom lifts
Skid-mounted compressors and generators
Utility trenchers and ground prep tools
Light-duty cranes or lifting hoists

In these machines, the 6B’s simplicity is key: fewer sensors, no turbo-related pressure or heat concerns, and predictable RPM behavior under varying load.

5. Oilfield and Utility Power Units

In the oil and gas sector, the 6B serves as a standalone utility engine for non-propulsion systems. Its predictable fuel consumption and mechanical durability make it well-suited for both temporary and permanent field installations.

Common Use Cases:

Mud mixing pump drives
Utility skid engines for lighting, compressors, or fluid transfer
Fuel pump drives for refueling operations
Winch and hydraulic power units
Oilfield monitoring system engines

The 6B’s non-electronic fuel system also simplifies integration with manual controls, relays, and pressure switches commonly used in these sectors.

6. Export and International Repower Applications

Because of its mechanical design and lack of emissions restrictions, the 6B remains in high demand for export markets and equipment repowering in developing regions.

Global Applications:

Generator exports to Latin America, Africa, and Asia
Agricultural machinery in non-regulated markets
Refurbished marine support engines
Engine swaps in legacy industrial machines
Repower projects for off-road and rail equipment

Its parts compatibility with the entire B Series family ensures continued support even in remote regions, and its long lifecycle keeps cost of ownership low over time.

Why Choose the Cummins 6B?

The 6B remains a trusted diesel platform for users who prioritize:

Mechanical Reliability – No ECUs, no emissions hardware, just proven direct injection and analog controls.
Ease of Servicing – Rebuildable in the field using widely available kits and basic tools.
Fuel Efficiency – Optimized for long, steady-duty cycles at moderate RPM.
Durability – Cast iron block and head, robust bottom end, long overhaul intervals.
Uptime – Fewer failure points and simpler operation compared to turbocharged alternatives.
Low Total Cost of Ownership – Lower initial cost, rebuildability, and affordable maintenance.
Ideal for Harsh Environments – Performs well in dusty, salty, or humid locations with minimal filtration needs.

Conclusion

The Cummins 6B engine offers a rugged, naturally aspirated alternative to turbocharged diesel platforms, making it ideal for marine auxiliary systems, industrial generators, agricultural equipment, and utility machines. With no electronics and no forced induction, the 6B represents a return to simple, reliable diesel power.

For operators in challenging environments, or for those maintaining older equipment in regions where emissions standards are not enforced, the 6B provides a dependable, low-maintenance solution. When paired with the right aftermarket support, this engine can easily exceed 15,000 hours of service—often with just routine maintenance and a midlife overhaul.