3679694
Regular Hexagon Jam Nut
Cummins®

The Cummins 3679694 Regular Hexagon Jam Nut is a specialized fastener designed for use in heavy-duty truck applications. Its purpose is to provide secure fastening in environments where vibrations and dynamic loads are common. This component is significant in maintaining the integrity and reliability of truck assemblies, ensuring that parts remain securely fastened under various operating conditions.

Basic Concepts of Regular Hexagon Jam Nuts

A regular hexagon jam nut is a type of lock nut that features a hexagonal shape, allowing it to be easily tightened and loosened using standard tools. Its design includes a nylon insert or a knurled surface that deforms under pressure, creating a locking mechanism that resists loosening due to vibrations. This type of nut is commonly used in applications where additional security is required to prevent fasteners from coming undone ¹.

Purpose and Role in Truck Operation

The Cummins 3679694 Regular Hexagon Jam Nut plays a role in the operation and maintenance of heavy-duty trucks by securing components and assemblies that are subject to significant stress and vibration. It is applied in various truck systems to ensure that critical parts remain firmly in place, contributing to the overall safety and performance of the vehicle. Its use is particularly important in areas such as the engine, transmission, and chassis, where secure fastening is vital ².

Key Features

The Cummins 3679694 Regular Hexagon Jam Nut is characterized by its hexagonal shape, which facilitates easy installation and removal using standard wrenches or sockets. It is composed of high-strength materials to withstand the rigors of heavy-duty applications. Unique design elements, such as a nylon insert or knurled surface, enhance its locking capabilities, providing additional resistance to loosening ³.

Benefits

Using the Cummins 3679694 Regular Hexagon Jam Nut offers several benefits. It provides improved fastening security, ensuring that components remain tightly fastened even in vibrating environments. Its design also offers resistance to vibration, reducing the likelihood of fasteners coming loose over time. Additionally, the ease of installation makes it a practical choice for maintenance and repair tasks.

Installation and Usage Guidelines

Proper installation of the Cummins 3679694 Regular Hexagon Jam Nut involves selecting the appropriate size and ensuring that the mating threads are clean and free of debris. It should be tightened to the recommended torque specifications using a torque wrench to ensure optimal performance. Best practices include periodically checking the tightness of the nut, especially in high-vibration areas, to maintain secure fastening.

Troubleshooting and Maintenance

Common issues with the Cummins 3679694 Regular Hexagon Jam Nut may include loosening due to excessive vibration or damage from over-tightening. Troubleshooting involves inspecting the nut and its mating threads for signs of wear or damage. Maintenance practices include regular checks for tightness and replacing the nut if it shows signs of significant wear or if the locking mechanism is compromised.

Cummins Overview

Cummins Inc. is a global power leader that designs, manufactures, and distributes engines, filtration, and power generation products. With a history of innovation and a strong reputation in the automotive industry, Cummins is committed to providing high-quality components that meet the demanding requirements of heavy-duty applications. The company’s focus on quality and performance ensures that its products, including the Cummins 3679694 Regular Hexagon Jam Nut, are reliable and effective in their intended uses.

Cummins Engine Compatibility with Part 3679694

The Regular Hexagon Jam Nut, part number 3679694, manufactured by Cummins, is a critical component in various engine configurations. This part is designed to secure and stabilize certain engine components, ensuring optimal performance and reliability. Below is a detailed overview of how this jam nut fits with the specified Cummins engines:

ISG Series

• ISG11 CM2880 G108
• ISG12 CM2880 G107
• ISG12 G CMOH6.0 G111

The ISG series engines, including the ISG11, ISG12, and the ISG12 G CMOH6.0, utilize the 3679694 jam nut in their assembly. This part is essential for securing various components within the engine, ensuring that they remain firmly in place under operational conditions.

ISX Series

• ISX CM570
• ISX CM870
• ISX CM871
• ISX15 CM2250
• ISX15 CM2250 SN
• ISX15 CM2350 X101

The ISX series engines, ranging from the ISX CM570 to the ISX15 CM2350 X101, incorporate the 3679694 jam nut in their design. This part is crucial for maintaining the integrity of the engine’s internal components, contributing to the overall durability and efficiency of the engine.

QSX Series

• QSX15 CM2250
• QSX15 CM2250 ECF
• QSX15 CM2350 X105

In the QSX series, including the QSX15 CM2250, QSX15 CM2250 ECF, and QSX15 CM2350 X105, the 3679694 jam nut plays a vital role. It is used to secure components that are subject to high stress and vibration, ensuring that these parts remain tightly fastened and operational.

X Series

• X11 CM2670 X126B
• X12 CM2350 X119B
• X12 CM2670 X121B
• X13 CM2670 X122B
• X15 CM2350 X116B
• X15 CM2350 X123B
• X15 CM2450 X134B

The X series engines, such as the X11 CM2670 X126B, X12 CM2350 X119B, and others up to the X15 CM2450 X134B, also integrate the 3679694 jam nut. This part is essential for the secure fastening of components that are critical to the engine’s performance and longevity.

The Regular Hexagon Jam Nut, part number 3679694, is a versatile and indispensable component in the Cummins engine lineup. Its application across various engine series underscores its importance in maintaining the structural integrity and operational efficiency of these engines.

Role of Part 3679694 Regular Hexagon Jam Nut in Engine Systems

The part 3679694 Regular Hexagon Jam Nut is instrumental in securing and maintaining the integrity of various engine components. Its primary function is to ensure that the components it connects remain firmly in place, thereby contributing to the overall stability and performance of the engine.

In the Cylinder Head assembly, the Regular Hexagon Jam Nut is often used to secure bolts that attach the cylinder head to the engine block. This connection is vital for maintaining the seal between the cylinder head and the engine block, which is essential for proper combustion and preventing leaks.

Within the Cylinder Top Level Assembly Head, the nut plays a role in fastening smaller components that are integral to the cylinder’s operation. This includes securing gaskets and seals that ensure the cylinder’s internal pressure is maintained efficiently.

The Rocker Lever system benefits from the Regular Hexagon Jam Nut by ensuring that the rocker levers are held in place with the required tension. This is important for the precise operation of the valve train, as any misalignment or looseness can lead to inefficient valve operation and potentially severe engine damage.

In the Rocker Lever Assembly, the nut is used to secure the rocker lever to its pivot point. This ensures that the lever can operate smoothly and with the correct amount of force, which is critical for the accurate opening and closing of the engine’s valves.

For the Rocker Lever Top Level Assembly, the Regular Hexagon Jam Nut is essential in maintaining the structural integrity of the assembly. It secures the various components that make up the top level of the rocker lever system, ensuring that they work in unison without any play or movement that could affect valve timing.

Lastly, in the Rocker Top Level Assembly Lever, the nut is used to fasten the lever to its mounting bracket. This connection is key to ensuring that the lever can transmit motion from the camshaft to the valves with minimal friction and maximum efficiency.

Overall, the Regular Hexagon Jam Nut is a small but significant component in the complex interplay of parts within an engine system. Its role in securing and maintaining the precise alignment and operation of these components is fundamental to the engine’s performance and longevity.

Conclusion

The Cummins 3679694 Regular Hexagon Jam Nut is a critical component in heavy-duty truck applications, providing secure fastening in environments with significant vibrations and dynamic loads. Its design, featuring a hexagonal shape and a nylon insert or knurled surface, ensures resistance to loosening and ease of installation. The nut’s application across various Cummins engine series underscores its importance in maintaining the structural integrity and operational efficiency of these engines. Proper installation, regular maintenance, and understanding its role in engine systems are essential for ensuring the reliability and performance of heavy-duty trucks.