Cummins QSB 5.9 Parts - Turbo Section

Turbocharger System Components for Cummins QSB 5.9 Engines

The Cummins QSB 5.9L is a proven, high-performance diesel engine used extensively in marine and industrial applications, where turbocharging plays a critical role in delivering power, efficiency, and responsiveness. A properly maintained turbo system ensures optimal boost pressure, efficient air intake, clean combustion, and extended engine life.

Diesel Pro Power offers a comprehensive selection of turbocharger components, supporting systems, and related gaskets, hoses, and seals designed specifically for the QSB 5.9’s single turbo configuration. All components are manufactured to OEM standards or better, ensuring a perfect fit and reliable service life.

Air Intake & Filtration for Turbocharged QSB 5.9 Engines

A turbocharger’s performance begins with the quality and volume of air entering the system. Restriction or contamination at the intake stage reduces efficiency and can lead to costly turbo damage.

Cummins AirSep System – Single Turbo Configuration

For marine operators looking to maximize clean air delivery to the turbocharger, the Cummins AirSep system is the gold standard. This all-in-one marine air filtration and crankcase ventilation system not only removes harmful particulates from incoming air but also prevents oil mist contamination in the intake.

• Optimized for QSB 5.9 Single Turbo Setups – Ensures unrestricted air flow while reducing oil carryover.

• Marine-Grade Filtration – Protects the turbocharger from corrosive salt-laden air.

• 4-Inch Throat Diameter – Matches standard QSB 5.9 marine intake connections for a secure fit.

• Reduced Engine Room Contamination – Captures blow-by gases and recirculates them efficiently.

Intake Manifold Sealing for Boost Integrity

Maintaining boost pressure requires perfect sealing throughout the intake system. Even small leaks in manifold covers, aftercoolers, or piping can reduce turbo efficiency, increase exhaust temperatures, and impact fuel economy.

Cummins Intake Manifold Cover Gasket

This precision-cut gasket seals the manifold cover to prevent boost pressure loss and maintain even air distribution across all cylinders.

• High-Temperature Resistant Material – Designed to withstand sustained turbocharged intake pressures.

• Marine-Grade Durability – Resistant to oil mist, vibration, and thermal cycling common in QSB 5.9 applications.

• Easy Installation – OEM-profile design ensures a precise fit without modification.

Aftercooler O-Rings for QSB 5.9

The aftercooler (also called an intercooler) is a key part of the turbo system, cooling compressed air before it enters the cylinders. O-rings ensure leak-free connections between the aftercooler housing and adjoining components.

Aftercooler O-Ring for QSB 5.9 Engines

• Leak Prevention Under Boost – Maintains a secure seal under high intake pressures.

• Heat-Resistant Elastomer Construction – Withstands elevated temperatures caused by turbo compression.

• Corrosion-Resistant – Ideal for saltwater marine environments.

Turbo Oil Drain System Components

A turbocharger’s bearings are lubricated by engine oil, which must be efficiently drained back to the sump. Any restriction or leak in this system can shorten turbo life.

Cummins Turbo Oil Drain Gasket

• Prevents Oil Leaks at the Drain Tube Connection – Maintains clean operation and prevents oil loss.

• High-Temperature Tolerance – Suitable for continuous high-load operation.

• Compatible with QSB 5.9 Marine & Industrial Engines – Ensures consistent lubrication return flow.

High-Temperature Jointing Compounds for Turbo Applications

High-performance turbocharged engines generate extreme exhaust and intake temperatures. Jointing compounds ensure a leak-free seal on flanges, housings, and manifolds exposed to these conditions.

Hi-Temperature Jointing Compound for Turbochargers

• Thermal Range up to 760°C – Suitable for exhaust manifold, turbo housing, and wastegate connections.

• Long-Term Stability – Remains effective under vibration and thermal expansion cycles.

• Marine & Industrial Proven – Works in demanding QSB 5.9 operating environments.

Turbocharger Hoses & Flexible Connections

Flexible hump hoses provide vibration isolation and allow for slight misalignment between turbo outlet piping and the charge-air cooler or intake manifold.

4" to 4" Turbo Hump Hose

• Marine-Grade Reinforced Silicone – Resistant to oil, saltwater mist, and heat.

• Flexible Center Section – Absorbs vibration and reduces stress on rigid piping.

• Sized for QSB 5.9 Single Turbo Systems – Ensures perfect fit and secure clamping.

Importance of Maintaining Turbocharger Components on the Cummins QSB 5.9

Proper turbo maintenance and timely replacement of supporting components can extend engine life, maintain peak horsepower, and prevent unplanned downtime. For marine applications, where reliability is critical, keeping the turbo system in top condition also supports better fuel economy and cleaner exhaust emissions.

Key best practices include:

• Regular inspection of air filtration systems for restriction or damage.

• Checking for boost leaks at gaskets, hoses, and clamps.

• Ensuring turbo oil lines are clean, unrestricted, and leak-free.

• Using only marine-grade sealing compounds and hoses for saltwater environments.