Cummins ISM Gasket Sets and Engine Sealing Components

The Cummins ISM engine is a workhorse in demanding environments—whether on-highway, off-road, or industrial. To ensure peak performance and prevent leaks in critical engine zones, gasket integrity is essential. Diesel Pro Power provides premium Cummins ISM gasket sets and sealing components that meet or exceed OEM standards. This page covers everything from full upper and lower gasket sets to individual gaskets for components like the rocker cover, oil pan, front cover, exhaust manifold, and more.

Why Gaskets Matter in the Cummins ISM Engine

Gaskets are responsible for sealing combustion pressures, coolant circuits, lubrication pathways, and exhaust flow. In an engine like the ISM, which undergoes extreme temperatures and high cylinder pressures, even the smallest leak can lead to costly damage. A reliable gasket prevents oil and coolant leaks, avoids loss of compression, and protects components from contamination.

Common issues resulting from failed gaskets include:

• Oil leaks from the rocker or oil pan
  
  

• Coolant leaks at liner seals or thermostat housings
  
  

• Exhaust leaks that cause power loss or overheating
  
  

• Combustion loss through cylinder head or intake manifold gaps
  
  

Whether you're completing a full engine rebuild or replacing a single component, Diesel Pro Power’s gasket options ensure dependable, long-lasting engine sealing.

Complete Upper Gasket Sets for Cummins ISM

An upper gasket set includes all major gaskets and seals located on the top half of the ISM engine, making it ideal for top-end rebuilds or repairs involving the cylinder head or intake system.

Included Components:

• Multi-layer steel cylinder head gasket
  
  

• Valve cover gaskets
  
  

• Injector O-rings and washers
  
  

• Rocker cover gaskets
  
  

• Intake and exhaust manifold gaskets
  
  

• Turbocharger mounting gaskets
  
  

• Thermostat housing gasket
  
  

• Valve stem seals
  
  

• Miscellaneous rubber and metal O-rings
  
  

Common Use Cases:

• Cylinder head removal and replacement
  
  

• Injector servicing
  
  

• Valve lash adjustment
  
  

• Top-end overhauls due to oil leaks or combustion loss
  
  

Installation Tips:

• Always clean the deck surface and inspect for warping
  
  

• Use manufacturer torque specs and tightening sequences
  
  

• Replace old fasteners if they show wear or corrosion
  
  

Complete Lower Gasket Sets for Cummins ISM

A lower gasket set is required when servicing the bottom end of the engine. These gaskets are responsible for maintaining oil flow integrity and preventing crankcase leaks.

Included Components:

• Oil pan gasket
  
  

• Front and rear crankshaft seals
  
  

• Gear cover seals
  
  

• Hand hole cover gaskets
  
  

• Oil cooler seals
  
  

• Water inlet and outlet gaskets
  
  

• Liner seal rings
  
  

• Rear structure seals
  
  

Recommended For:

• In-frame overhauls
  
  

• Main and rod bearing replacements
  
  

• Rear main seal servicing
  
  

• Crankshaft or oil pump work
  
  

• Oil pan removal
  
  

Best Practices:

• Inspect mating surfaces for gouges or pitting
  
  

• Use non-hardening sealants where specified
  
  

• Replace seals in one motion to avoid tearing
  
  

Cylinder Liner Seal Rings for Cummins ISM

Cylinder liner seal rings sit at the base of each wet sleeve liner and are crucial to separating engine oil and coolant. Over time, these seals degrade due to thermal cycling, leading to coolant leakage into the crankcase.

Symptoms of Failed Liner Seals:

• Milky oil or rising oil levels
  
  

• Overheating
  
  

• Coolant loss without visible leaks
  
  

• Excessive white smoke
  
  

Replacement Guidelines:

• Always install new liner seals during an in-frame overhaul
  
  

• Lubricate seals with assembly lube before installation
  
  

• Check liner protrusion and seating height before torquing
  
  

Oil Pan Gasket for Cummins ISM

The oil pan gasket seals the joint between the oil pan and the engine block. Cummins ISM engines with external crankshaft dampers require a specific oil pan gasket design to accommodate vibrations and dimensional changes.

Features:

• High-temp and oil-resistant material
  
  

• Reusable options available in some configurations
  
  

• Reduces oil leaks from lower engine area
  
  

Common Applications:

• Oil leak repair at pan-to-block seam
  
  

• Oil pump servicing
  
  

• In-frame engine rebuilds
  
  

Exhaust Manifold Outlet Gaskets

These gaskets seal the high-temperature junction between the exhaust manifold and turbo outlet or downpipe. A leaking exhaust gasket can result in:

• Turbo inefficiency
  
  

• Loss of backpressure
  
  

• Burnt engine components nearby
  
  

Key Benefits:

• Multi-layered steel construction for heat resistance
  
  

• Precision-fit for ISM engine manifold geometry
  
  

• Easy to install with standard hand tools
  
  

Rocker Cover and Rocker Housing Gaskets

The ISM engine features both a rocker cover gasket and a separate rocker housing gasket. These gaskets prevent oil leakage from the top of the cylinder head and provide a barrier for pressurized oil flowing through the valvetrain.

Material Characteristics:

• Rubber or composite materials with heat-resistant coating
  
  

• Compatible with later-style ISM configurations
  
  

• Designed for simple removal and resealing
  
  

Replacement Timing:

• During valve lash adjustments
  
  

• When changing injectors or inspecting rocker arms
  
  

• Anytime oil is found around the cylinder head perimeter
  
  

Front Gear Cover and Seal Gaskets

The gear cover and front crankshaft seal must withstand constant rotation and exposure to oil spray. These gaskets provide a tight seal around the camshaft and crankshaft geartrain area.

Common Symptoms of Failure:

• Oil sling on the front of the engine
  
  

• Damp or dirty gear cover exterior
  
  

• Low oil levels over time
  
  

Tips for Replacement:

• Use a wear sleeve if the crankshaft has scoring
  
  

• Verify alignment of gear cover prior to tightening bolts
  
  

• Use a high-tack sealant to ensure proper adhesion
  
  

Intake and Turbo Mounting Gaskets

From intake elbow gaskets to turbocharger oil feed seals, Diesel Pro Power offers all sealing components required for ISM air and fuel delivery systems. These gaskets ensure that no pressurized air or oil leaks occur during turbo operation.

Common Causes for Replacement:

• Boost pressure drop
  
  

• Oil dripping around turbo base
  
  

• Whistling or hissing noises under load
  
  

Best Practices:

• Always replace gaskets when removing the turbo
  
  

• Clean both mating flanges before reassembly
  
  

• Use torque specs to prevent overtightening
  
  

Oil Cooler Gaskets

The oil cooler regulates temperature in the ISM's high-pressure lubrication system. Its mounting gasket ensures a tight seal between the cooler housing and engine block.

Key Benefits:

• Prevents oil and coolant cross-contamination
  
  

• Withstands high thermal cycles
  
  

• Sold individually—2 per cooler required
  
  

Replacement Tip:
Use new gaskets during any oil cooler replacement or cleaning. Check for corrosion at mounting surfaces.

Thermostat Housing Gasket

The thermostat housing gasket seals the joint between the cylinder head and the thermostat outlet. A leak here can result in significant coolant loss and poor temperature regulation.

Recommended Replacement When:

• Thermostat is stuck or being replaced
  
  

• Coolant is leaking around the housing
  
  

• Performing top-end service
  
  

Hand Hole Gaskets

These rectangular or oval gaskets seal access ports used for visual inspection or maintenance. They are often replaced during bottom-end rebuilds.

Accessory Sealants & Gasket Makers for Cummins ISM

To ensure a lasting repair, Diesel Pro Power also stocks high-performance gasket sprays and RTV sealants. These support a wide variety of ISM applications, including sealing oil pans, front covers, water pumps, and custom joints.

Sealant Types Available:

• High-temp RTV silicone – Ideal for turbo areas
  
  

• Sensor-safe RTV – Designed for use around electronics
  
  

• Non-hardening pliable sealant – Used on stamped metal covers
  
  

• Cold weld epoxy – Reinforces worn castings or fills gaps
  
  

• High tack gasket spray – Secures gaskets during assembly
  
  

• Liquid threadlocker (red) – Prevents bolt loosening from vibration
  
  

Diesel Pro Power: Your Source for ISM Gasket Solutions

Whether you’re looking for a full Cummins ISM upper and lower gasket set, or just a single seal for an oil cooler or thermostat housing, Diesel Pro Power carries what professionals trust. Our parts are in stock, ready to ship, and backed by over 40,000 satisfied customers worldwide.

Why Choose Us:

• Premium-quality aftermarket and OEM-equivalent gaskets
  
  

• Fast worldwide shipping
  
  

• Expert customer service from diesel specialists
  
  

• Fully stocked inventory for Cummins L10, M11, and ISM