3920854
Captive Washer Cap Screw
Cummins®

The Captive Washer Cap Screw 3920854 by Cummins is a specialized fastener designed for use in commercial truck operations. This screw plays a crucial role in securing various components within the truck’s engine and chassis systems. Cummins Inc., a leader in the automotive industry, is renowned for its diesel engines and related technologies, contributing significantly to the efficiency and reliability of commercial vehicles ².

Basic Concepts of Captive Washer Cap Screws

A Captive Washer Cap Screw is a type of fastener that incorporates a washer directly into the screw head or shank. This design ensures that the washer remains in place during installation, providing a consistent sealing surface and reducing the risk of the screw loosening over time. In mechanical assemblies, these screws are used to secure components that require a tight, vibration-resistant connection. The washer plays a critical role in distributing the load and preventing damage to the surfaces being joined ³.

Purpose and Function of 3920854 Captive Washer Cap Screw

The 3920854 Captive Washer Cap Screw is specifically designed for truck applications, where it contributes to the integrity and reliability of various components. This screw is used in environments where vibrations and dynamic loads are common, ensuring that critical connections remain secure. By providing a stable and sealed connection, it helps maintain the structural integrity of the truck’s engine and chassis systems ⁴.

Key Features

The 3920854 Captive Washer Cap Screw boasts several key features that enhance its performance in heavy-duty applications. It is constructed from high-strength materials, ensuring durability under demanding conditions. The design includes a captive washer that is integrated into the screw, simplifying the installation process and ensuring consistent performance. Additionally, the screw features a corrosion-resistant coating, which protects it from the harsh environments often encountered in commercial truck operations ¹.

Benefits

Using the 3920854 Captive Washer Cap Screw offers several advantages. The integrated washer provides an effective sealing surface, which helps prevent leaks and maintain the integrity of connections. The screw’s resistance to vibration ensures that it remains securely fastened, even in dynamic operating conditions. Furthermore, the ease of installation reduces the time and effort required during maintenance, contributing to the overall efficiency of truck operations. These benefits enhance the safety and reliability of the vehicle ².

Troubleshooting and Maintenance

Common issues associated with Captive Washer Cap Screws include loosening due to vibration and corrosion. To troubleshoot these problems, it is important to inspect the screws regularly for signs of wear or damage. If corrosion is detected, the affected screws should be replaced to prevent further degradation. Maintenance practices such as applying a thread locker can help ensure the longevity and optimal performance of the screws. Additionally, using the correct torque specifications during installation will help maintain the integrity of the connections ³.

About Cummins

Cummins Inc. has a long-standing reputation for excellence in the automotive industry. Founded in 1919, the company has been at the forefront of diesel engine technology, providing innovative solutions for commercial vehicles. Cummins is committed to quality and innovation, continually advancing their product offerings to meet the evolving needs of the industry. Their expertise in engine and component design ensures that their products, like the 3920854 Captive Washer Cap Screw, deliver reliable performance in demanding applications ⁴.

Cummins Captive Washer Cap Screw 3920854 Compatibility

The Cummins Captive Washer Cap Screw part number 3920854 is a versatile component designed to fit a variety of Cummins engines. This part is integral in securing various engine components, ensuring they remain tightly fastened and properly aligned during operation. Below is a detailed breakdown of the engines with which this part is compatible:

Cummins 4 Series Engines

• 4B3.9
• B4.5
• B4.5 RGT

These engines, part of the smaller 4 Series lineup, benefit from the 3920854 screw in applications where securing smaller components is necessary.

Cummins 6 Series Engines

• 6B5.9
• 6C8.3
• B5.6 CM2670 B152B
• B6.7S
• ISBE CM2150
• ISBE CM800
• ISBE4 CM850
• ISC CM2150
• ISC CM554
• ISC CM850
• ISC8.3 CM2250

The 6 Series engines, known for their robustness and power, utilize the 3920854 screw in various applications. This includes securing larger components and ensuring the integrity of critical engine assemblies.

Cummins F Series Engines

• F2.8 CM2620 F135B
• F4.5 CM2620 F139B
• F4.5 CM2620 F141C

The F Series engines, often used in specialized applications, also incorporate the 3920854 screw. This part ensures that the specific configurations and components of these engines are held securely.

Cummins ISB and ISD Engines

• ISB (Chrysler)
• ISB CM550
• ISB CM850
• ISB/ISD4.5 CM2150 B119
• ISB/ISD6.7 CM2150 SN
• ISB5.9 CM2880 B110
• ISB5.9 CM2880 B140
• ISB5.9 CM2880 B149

The ISB and ISD engines, known for their durability and performance, use the 3920854 screw in numerous applications. This includes securing both large and small components, ensuring the engine’s structural integrity.

Role of Part 3920854 Captive Washer Cap Screw in Engine Systems

The Part 3920854 Captive Washer Cap Screw is integral to the secure assembly and operation of various engine components. Its application ensures that connections remain tight and secure, which is essential for the proper functioning of the engine system.

Air and Fuel Systems

In the air fuel control plumbing and fuel plumbing, the Captive Washer Cap Screw is used to fasten components securely, preventing leaks and ensuring that the air-fuel mixture is delivered consistently to the engine. This is particularly important in the fuel line kit and fuel filter plumbing, where any loose connection could result in fuel leakage or inconsistent fuel delivery.

The air intake connection also benefits from the secure fastening provided by this screw, ensuring that the air intake system is sealed properly, which is vital for maintaining the correct air-fuel ratio.

Fuel Delivery and Management

Within the Bosch fuel pump kit and fuel pump conversion kit, the Captive Washer Cap Screw plays a role in securing the fuel pump to its mounting bracket, ensuring stability and preventing vibrations that could affect fuel delivery.

In the fuel manifold and injector fuel supply tube, this screw ensures that the fuel injectors are mounted securely, which is essential for precise fuel injection timing and quantity.

Engine Control and Monitoring

The engine control module (ECM) and its location are secured using the Captive Washer Cap Screw, ensuring that the ECM remains in place and is not affected by engine vibrations. This is important for the reliable operation of the engine monitoring system, which relies on stable and accurate data from the ECM.

Lubrication and Performance

In the lubricating oil supply tube, the screw ensures that the oil lines are securely fastened, which is essential for maintaining proper lubrication throughout the engine. This is particularly important in performance parts where enhanced lubrication is often required.

Exhaust and Emission Control

The exhaust recirculation system also utilizes this screw to ensure that the recirculation valve and associated plumbing are securely fastened, which helps in reducing emissions by recirculating a portion of the exhaust gas back into the intake.

Additional Applications

The Captive Washer Cap Screw is also used in the power take-off assembly to secure components, ensuring that the assembly functions correctly and efficiently. In the pressure sensor applications, it ensures that the sensor is mounted securely, providing accurate readings for engine management.

Conclusion

Overall, the Part 3920854 Captive Washer Cap Screw is a versatile fastener that plays a significant role in ensuring the secure and reliable operation of various engine components. Its compatibility with a wide range of Cummins engines and its key features make it an essential component for maintaining the structural integrity and operational efficiency of these engines.