Parts For Cummins QSB 5.9 Marine Engines

The Cummins QSB 5.9 engine is a top choice for marine propulsion systems due to its proven reliability, compact design, and smooth, quiet power output. Whether you operate a recreational boat, commercial workboat, or generator-driven vessel, this engine brings together performance and comfort for a superior on-water experience. Diesel Pro Power offers a full range of Cummins QSB 5.9 parts, shipped worldwide within 24 hours.

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.

Applications for the Cummins QSB 5.9 Engine

Marine Propulsion and Auxiliary Systems

The QSB 5.9 is specifically designed for use in the following types of vessels and marine systems:

• Cruisers and Yachts – Quiet, clean, and efficient power for long-range cruising

• Fishing Boats – Durable and easy to maintain under constant use

• Pilot Boats and Tenders – Fast torque response and excellent maneuverability

• Workboats and Commercial Vessels – High uptime with minimal emissions

• Onboard Generators – Reliable marine auxiliary power for pumps, lighting, HVAC

Its adaptability makes it suitable for both new vessel builds and repowers.

Full Range of Cummins QSB 5.9 Parts

Diesel Pro Power stocks a wide range of Cummins QSB 5.9 parts and accessories—everything you need to support repairs, overhauls, or performance upgrades.

Rebuild Kits for Cummins QSB 5.9

If you're performing an engine overhaul, our rebuild kits save time and reduce error. Available kits include:

• Piston Kits – With rings, retainers, and pins

• Upper and Lower Gasket Sets – For head reseal and crankcase integrity

• Crankshaft Shell Sets – Main and rod bearing sets

• Complete Rebuild Kits – Everything you need in one comprehensive package

Also available:

• Seal kits

• Cleaning solutions

• Installation tools and filter wrenches

Each component is precision-made and marine-grade, offering superior sealing and durability.

Fresh Water Pumps for Cummins QSB 5.9

Keep your engine at safe operating temperature with our cooling solutions:

• Fresh water pumps

• Pump seals and o-rings

• Thermostat kits

• Radiator cleaners

All pumps are covered by warranty and are engineered to resist marine corrosion and scaling.

Seawater System Parts for Cummins QSB 5.9

Raw water cooling systems require dependable flow and corrosion resistance. We carry:

• Raw water pump assemblies

• Thermostats and bypass fittings

• Zinc anodes for corrosion control

• Hose connections and clamps

These components are designed specifically for saltwater environments and built to handle high flow rates.

Cylinder Heads for Cummins QSB 5.9

Cylinder heads play a vital role in maintaining power and fuel economy. Our inventory includes:

• Heads with and without valves or springs

• Valve springs, seals, and retainers

• Head bolts and cover gaskets

Machined to OEM specifications and tested for pressure and flatness.

Additional Cummins QSB 5.9 Engine Parts

We offer more than just core components. Our full catalog includes:

Gaskets and Seals

• Full gasket sets

• Valve cover gaskets

• Oil pan gaskets

• Thermostat housing gaskets

Made with marine-grade materials that withstand high heat and vibration.

Connecting Rods

• OEM-spec rods

• Bearing sets

• Wrist pin bushings

Precision-balanced for long service life and smooth engine operation.

Oil and Fuel Filters

• Spin-on oil filters

• Marine-rated fuel filters

• Water separators

• Filter mounting bases

Designed to catch contaminants without restricting flow—ideal for clean marine operation.

Paints, Sealants, and Cleaners

• Cummins red and black engine enamel

• Threadlockers and RTV sealants

• Gasket adhesives

• Engine degreasers and radiator flush

Keep your engine clean, protected, and looking new.

Why Buy Your Cummins QSB 5.9 Parts from Diesel Pro Power?

24-Hour Worldwide Shipping

We understand the urgency of marine repairs. All orders ship within 24 hours, and we deliver to ports, marinas, and shipyards across the globe.

Easy-to-Navigate Website

Quickly find the right part with our fast-loading, intuitive online catalog. Filter by category, part function, or visual reference. It’s designed to save time for marine technicians and DIYers alike.

Great Reviews from Real Customers

Our reviews speak for themselves. Thousands of marine operators, engineers, and captains trust Diesel Pro Power for their critical engine needs. Read reviews to learn how we’ve helped customers across 130+ countries.

Over 40,000 Satisfied Customers

We’ve built our reputation on relationships. From a single seal to full rebuild kits, we provide unmatched service and quality to every customer.

Excellent Customer Service

Our team includes diesel engine specialists who understand marine power. Whether you’re troubleshooting or confirming a fit, we’re available by phone or email to walk you through your options.

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