Cummins ISB 5.9 Gasket Kit Catalog

The Cummins ISB 5.9 engine is a proven workhorse in marine, industrial, and power generation applications. One of the keys to maintaining peak performance is ensuring a proper seal across all components—and that starts with using high-quality gasket kits and sealing products. This catalog covers upper gasket sets, lower gasket sets, and individual sealsdesigned for the ISB 5.9 platform, along with compatible products for related 4B, 6B, ISB 4.5, ISB 6.7, QSB 4.5, and QSB 6.7 engines.

Complete Gasket Kits for Cummins ISB 5.9

Upper Gasket Set for Cummins ISB 5.9

The upper gasket set contains all major sealing components needed for a top-end rebuild or head replacement. This includes cylinder head gaskets, intake and exhaust manifold gaskets, valve cover gaskets, and associated O-rings and seals. Designed for precision fitment, these gaskets maintain compression, prevent coolant and oil leaks, and ensure clean air and exhaust flow.

Applications:

• Cylinder head service

• Valve train work

• Top-end overhauls

Lower Gasket Set for Cummins ISB 5.9

The lower gasket set is tailored for bottom-end repairs, including the crankshaft seals, oil pan gasket, water pump seals, and other critical sealing points. By using high-quality materials resistant to oil, fuel, and coolant, these gaskets ensure reliable operation even under heavy-duty conditions.

Applications:

• Oil pan resealing

• Crankshaft repairs

• Bottom-end overhauls

Individual Cummins ISB 5.9 Gaskets & Seals

Oil Pick-Up Tube Gasket

A precision-cut gasket that seals the oil pick-up tube to prevent air entry into the lubrication system. Compatible with multiple Cummins models including 4B, 6B, ISB, and QSB engines.

Intake Manifold Cover Gasket

Ensures a proper seal between the intake manifold cover and the cylinder head. Prevents unmetered air from entering the engine, which can impact fuel efficiency and emissions.

Aftercooler O-Ring

A specialized O-ring designed to seal the aftercooler connections. Compatible with multiple Cummins B-Series and ISB/QSB engines. Resistant to temperature changes and boost pressure.

Valve Cover Gasket

Provides a leak-free seal for the valve cover, preventing oil seepage and maintaining clean engine operation. Built from heat-resistant material for long service life.

Cover Plate Gasket

Used on various Cummins applications to seal cover plates on the engine block. Helps maintain oil and coolant integrity.

Fuel Injection Pump Gasket

Prevents fuel leaks at the injection pump mounting surface. This gasket is cut to tight tolerances to withstand fuel system pressures.

Oil Cooler Cover Gaskets

Available in multiple designs to fit different Cummins oil cooler housings. These gaskets ensure a secure seal between the oil cooler and its cover, preventing oil and coolant cross-contamination.

Turbo Oil Drain Gasket

Seals the turbocharger oil drain connection to the engine, preventing oil leaks that could cause turbo or engine damage.

Oil Cooler Core Gasket

A metal gasket engineered for durability in the high-pressure oil cooler circuit. Helps maintain oil temperature regulation by preventing leaks.

Water Pump Seal Ring

Prevents coolant leaks at the water pump mounting area. Made from high-quality elastomers resistant to temperature extremes.

Thermostat Seal

Ensures a tight fit for the thermostat, maintaining correct coolant flow and engine operating temperature.

Specialty Sealants & Compounds

High-Temperature Jointing Compound

A premium sealant for turbocharger and exhaust applications. Withstands extreme heat (up to 760°C) and provides a durable, gas-tight seal.

High Tack Gasket Spray

A fast-drying spray that holds gaskets in place during assembly while improving the long-term seal. Ideal for irregular or pitted surfaces.

3H Gasket Maker

A liquid sealant designed for use in oil and coolant systems. Remains flexible after curing and resists cracking.

High-Strength Threadlocker

A red, high-strength compound for securing threaded fasteners that are subject to vibration. Ideal for turbocharger and exhaust manifold bolts.

Silicone Sensor-Safe Gasket Maker

A blue RTV silicone that resists oil and coolant exposure while remaining safe for engine sensors.

J-B Weld Cold Weld

A steel-reinforced epoxy for repairing cracks in metal engine components. Withstands high temperatures and mechanical stress.

High-Temp RTV Silicone Gasket Maker

Formulated for high-temperature sealing in exhaust and turbo systems. Creates a flexible, oil-resistant seal.

Ultra Blue RTV Silicone Gasket Maker

A versatile silicone sealant that is sensor-safe and oil-resistant. Commonly used in oil pans, valve covers, and water pumps.

Non-Hardening Pliable Sealant

Remains soft and pliable after curing, making it ideal for sealing components that require periodic disassembly.

Choosing the Right Cummins ISB 5.9 Gasket Kit

Selecting the correct gasket or seal for your ISB 5.9 engine depends on the type of repair you’re performing:

• Top-end work → Use the upper gasket set

• Bottom-end work → Use the lower gasket set

• Component-specific repairs → Select individual gaskets or O-rings

• Extreme temperature areas → Consider specialized sealants or jointing compounds

Maintenance Tips for Longer Gasket Life

1. Clean mating surfaces thoroughly before installing a gasket to ensure a proper seal.

2. Torque bolts to factory specifications to avoid crushing or uneven sealing.

3. Inspect related components—warped surfaces can cause repeated gasket failures.

4. Use recommended sealants in applications where gaskets alone are not sufficient.

5. Replace gaskets proactively during major overhauls to prevent future downtime.