Cummins QSB 4.5 Exhaust System Parts Catalog

The Cummins QSB 4.5 engine is widely used in marine and industrial applications where dependable exhaust system performance is essential for both safety and efficiency. Whether installed in a commercial vessel, power generation set, or industrial equipment, maintaining your exhaust components is critical for optimal operation, emission control, and noise reduction.

This catalog covers exhaust system parts designed for the Cummins QSB 4.5, with a focus on durable, OEM-quality components for both marine and stationary applications. From manifold gaskets to mufflers, each item is engineered to withstand the demanding heat cycles and vibration typical of heavy-duty diesel operation.

Intake & Exhaust Manifold Components

Intake Manifold Cover Gasket for Cummins QSB 4.5

A high-quality intake manifold cover gasket ensures an airtight seal between the intake manifold cover and the manifold body, preventing air leaks that could reduce engine efficiency or cause improper fuel-air mixture ratios.

• Material: Heat-resistant composite designed to withstand thermal expansion.

• Applications: Ideal for marine propulsion, auxiliary power units, and industrial machinery using the Cummins QSB 4.5.

• Benefits: Maintains peak airflow integrity, reduces risk of unmetered air entry, and ensures consistent engine performance.

Exhaust Manifold Insulation & Heat Management

Exhaust systems in marine and industrial environments require effective thermal control to improve safety, reduce heat transfer to surrounding components, and protect crew members in close-quarters engine rooms.

3" Wide Exhaust Manifold Insulation Tape (100 ft, 1/8" Thick)

This manifold insulation tape is designed for wrapping exhaust manifolds and piping, reducing surface heat and preventing radiant heat damage to nearby wiring, hoses, and components.

• Dimensions: 3 inches wide × 100 feet long × 1/8 inch thick.

• Material: High-temperature fiberglass composite with excellent thermal insulation properties.

• Marine Benefit: Reduces ambient engine room temperature, improving comfort and equipment reliability.

4" Wide Exhaust Manifold Insulation Tape (100 ft, 1/8" Thick)

A wider variant of the exhaust insulation tape, ideal for covering larger diameter exhaust piping or providing quicker coverage of long sections.

• Dimensions: 4 inches wide × 100 feet long × 1/8 inch thick.

• Heat Resistance: Maintains integrity at sustained exhaust temperatures.

• Application Tip: Commonly used on commercial marine engines to meet Coast Guard or classification society thermal safety standards.

Exhaust Flanges & Gaskets

4" Industrial Exhaust Manifold Flange

A precision-machined 4-inch inside diameter exhaust flange provides a secure connection point between the exhaust manifold and downstream exhaust piping.

• Design: Industrial-grade steel for corrosion resistance and vibration tolerance.

• Use Case: Ideal for marine and stationary generator exhaust systems requiring high clamp loads without warping.

Gasket for 4" Exhaust Flange

An industrial exhaust flange gasket designed to create a leak-free seal between the manifold flange and exhaust piping.

• Material: Heat-resistant graphite composite.

• Benefit: Prevents exhaust gas leaks, reducing harmful emissions in enclosed spaces like marine engine rooms.

Mufflers & Silencers

4" Muffler for Industrial and Marine Diesel Engines

Heavy-duty industrial engine muffler with a 4" National Pipe Thread inlet and outlet, designed to reduce exhaust noise without restricting gas flow.

• Construction: Welded steel housing with internal baffles.

• Marine Suitability: Corrosion-resistant coating to withstand high-humidity, salt-laden environments.

• Performance Note: Proper muffler sizing helps maintain turbocharger efficiency and prevents excessive backpressure.

Exhaust End Caps & Rain Protection

3" Cap for Engine Muffler

A pipe cap designed to protect the muffler outlet when the engine is idle, preventing water ingress in marine settings and debris intrusion in industrial sites.

• Outside Diameter: 2.99" (7.59 cm).

• Material: Weather-resistant metal with a secure fit.

3.5" Cap for Engine Muffler

Slightly larger cap for mufflers with a 3.5-inch outlet diameter.

• Outside Diameter: 3.50" (8.89 cm).

• Marine Benefit: Helps prevent rainwater or spray from entering exhaust piping during idle or shutdown.

4.5" Cap for Engine Muffler

Designed for mufflers with a 4.49" (11.40 cm) outside diameter.

• Application: Frequently used in commercial marine exhaust systems where topside exhaust outlets are exposed to weather.

5" Cap for Engine Muffler

Largest standard exhaust cap in this range, with a 5-inch outside diameter.

• Durability: Designed for heavy-duty marine exhaust stacks.

• Protection Role: Prevents engine damage caused by water intrusion in tidal or wet dock conditions.

Gauge Monitoring for Exhaust System Health

While not a direct exhaust component, mechanical and electric gauges play an important role in monitoring exhaust gas temperature (EGT) and other parameters affecting exhaust system longevity.

• Mechanical Gauges: Rugged, no-power-needed units suitable for harsh environments.

• Electrical Gauges: Available in 12V or 24V for integration with existing marine electrical systems.

• Safety Tip: High EGT readings can indicate turbocharger or exhaust restriction issues—addressing them promptly prevents costly failures.