3904383
Hexagon Head Cap Screw
Cummins®

The 3904383 Hexagon Head Cap Screw, manufactured by Cummins, is a specialized fastener designed for use in commercial trucks. Cummins, a well-established name in the commercial truck industry, produces a range of components that ensure the reliability and efficiency of truck operations. This Cummins part is integral to various fastening applications within commercial trucks, contributing to the secure assembly of critical components.

Basic Concepts of Hexagon Head Cap Screws

A Hexagon Head Cap Screw is a type of fastener characterized by its hexagonal head, which allows for efficient tightening and loosening using a wrench or socket. These screws are commonly used in applications requiring a high degree of torque and secure fastening. Mechanically, the hexagonal head design provides a stable interface for tools, reducing the risk of cam-out and ensuring consistent torque application. The cap screw variant typically features a threaded shank that extends through the components being joined, with a smooth shank above the threads to prevent galling and ensure smooth installation ¹.

Purpose of the 3904383 Hexagon Head Cap Screw in Truck Operation

This part plays a significant role in the operation and maintenance of commercial trucks. It is utilized in various truck components, including engine mounts, transmission housings, and chassis assemblies. By providing a secure and reliable fastening solution, this screw helps maintain the structural integrity and alignment of critical truck parts. Its application ensures that components remain firmly in place under the dynamic loads and vibrations experienced during truck operation.

Key Features

The 3904383 is designed with several key features that enhance its functionality and durability. It is composed of high-strength materials, typically alloy steel, which provides excellent tensile strength and resistance to wear. The screw features a fine or coarse thread, depending on the specific application, allowing it to grip securely into the mating material. The hexagonal head design ensures easy and efficient tightening with standard tools, while the cap screw style prevents damage to the fastened components during installation.

Benefits

Using this Cummins part offers several benefits. Its high-strength material composition and precise thread design contribute to enhanced fastening security, reducing the risk of loosening over time. The screw’s resistance to corrosion and wear ensures long-term reliability in demanding truck environments. Additionally, its compatibility with various truck components makes it a versatile fastening solution for different applications within commercial trucks.

Installation Guidelines

Proper installation of the 3904383 is crucial for ensuring its effectiveness and longevity. To install, first, ensure that the mating surfaces are clean and free of debris. Use a torque wrench to apply the specified torque, which varies depending on the application and material being fastened. It is recommended to use a socket or wrench that fits the hexagonal head precisely to avoid rounding the corners. For optimal performance, it is advisable to apply a thread locker or anti-seize compound to the threads, depending on the environment and application requirements ².

Troubleshooting and Maintenance

Common issues with this part may include loosening due to vibration or corrosion. Regular inspection and re-torquing can help maintain the screw’s integrity. If corrosion is detected, cleaning the affected area and reapplying a suitable protective coating can prevent further degradation. In cases where the screw shows signs of wear or damage, replacement with a new screw is recommended to ensure continued secure fastening.

Cummins Overview

Cummins is a renowned manufacturer in the commercial truck industry, with a history of producing high-quality components that enhance the performance and reliability of trucks. The company offers a broad range of products, including engines, transmissions, and aftermarket parts, all designed to meet the rigorous demands of commercial trucking. Cummins’ reputation for durability, efficiency, and innovation makes its components, such as the 3904383, a preferred choice for truck manufacturers and maintenance professionals.

Cummins Part 3904383: Hexagon Head Cap Screw in Engine Applications

The Cummins part 3904383, a Hexagon Head Cap Screw, is a critical component utilized across a variety of engine models. This screw is designed to provide secure fastening in high-stress environments, ensuring the integrity and reliability of engine assemblies.

Application in Specific Engine Models

• 4B3.9 and 6B5.9 Engines

  In the 4B3.9 and 6B5.9 engines, the Hexagon Head Cap Screw is employed to secure various engine components, ensuring that parts remain tightly fastened under operational stress. This is crucial for maintaining the structural integrity of the engine and preventing any potential loosening or failure during operation.

• B4.5 RGT Engine

  The B4.5 RGT engine also utilizes the Hexagon Head Cap Screw for similar purposes. Its application in this engine model is vital for the assembly of components that are subject to significant mechanical forces and thermal stresses.

• F2.8 CM2620 F135B, ISF2.8 CM2220 F117, and ISF2.8 CM2220 F129 Engines

  These engines, including the F2.8 CM2620 F135B, ISF2.8 CM2220 F117, and ISF2.8 CM2220 F129, incorporate the Hexagon Head Cap Screw in their design. The screw is used to fasten parts that require precise alignment and secure fastening, ensuring the engine operates efficiently and reliably.

• QSB4.5 CM850 (CM2850) Engine

  The QSB4.5 CM850 (CM2850) engine also relies on the Hexagon Head Cap Screw for its assembly. This engine model, like others, benefits from the screw’s ability to maintain tight fastenings, which is essential for the engine’s performance and longevity.

Grouping of Engines

The engines listed can be grouped based on their similar applications of the Hexagon Head Cap Screw:

• 4B3.9 and 6B5.9 Engines: These engines use the screw for securing components under operational stress.
• B4.5 RGT Engine: This engine model also relies on the screw for securing parts that require precise fastening.
• F2.8 CM2620 F135B, ISF2.8 CM2220 F117, and ISF2.8 CM2220 F129 Engines: These engines incorporate the screw for fastening parts that need precise alignment and secure fastening.
• QSB4.5 CM850 (CM2850) Engine: This engine model benefits from the screw’s ability to maintain tight fastenings, ensuring efficient and reliable operation.

Role of Part 3904383 Hexagon Head Cap Screw in Engine Systems

In the intricate assembly of engine systems, the 3904383 plays a significant role in ensuring the secure attachment and reliable operation of various components.

Compressor and Freon Connection

The compressor is a vital component in the air conditioning system, responsible for compressing the refrigerant (freon) to facilitate the cooling process. The Hexagon Head Cap Screw is utilized to fasten the compressor to its mounting bracket, ensuring stability and minimizing vibrations that could affect performance. Additionally, it secures the freon connection points, maintaining the integrity of the refrigerant pathway and preventing leaks.

Exhaust Outlet

In the exhaust system, the Hexagon Head Cap Screw is employed to attach the exhaust outlet to the engine block or manifold. This secure connection is essential for directing exhaust gases away from the engine, contributing to efficient engine operation and reducing emissions.

Drive Mechanism

The drive mechanism, which includes components like the timing belt or chain, relies on the Hexagon Head Cap Screw to fasten pulleys, sprockets, and other drive components. This ensures precise alignment and tension, which are vital for the smooth operation of the engine’s various subsystems.

Fan and Fan Support

The cooling fan and its support structure are critical for maintaining optimal engine temperature. The Hexagon Head Cap Screw is used to secure the fan to its housing and the support structure to the engine, ensuring that the fan operates efficiently and remains stable under varying conditions.

Fuel Pump

In fuel delivery systems, the Hexagon Head Cap Screw is utilized to attach the fuel pump to the fuel tank or mounting bracket. This secure attachment is essential for maintaining the pump’s position and ensuring consistent fuel delivery to the engine.

Conclusion

Overall, the 3904383 is a fundamental component in the assembly and operation of various engine systems, contributing to the stability, efficiency, and reliability of the engine as a whole. Its robust design and versatile application make it an essential part in the maintenance and operation of commercial trucks.