3648651
Twelve Point Cap Screw
Cummins®

The Twelve Point Cap Screw, identified by Part #3648651, is a specialized fastener produced by Cummins, a renowned manufacturer in the automotive and heavy-duty truck industry. This screw plays a significant role in the maintenance and assembly of heavy-duty trucks, ensuring the secure attachment of various components and contributing to the overall structural integrity of the vehicle.

Basic Concepts and Functionality

A Twelve Point Cap Screw is a type of fastener characterized by its twelve-sided socket head, which allows for more precise and efficient tightening compared to traditional hex-head screws. This design reduces the likelihood of cam-out, where the tool slips out of the fastener head during tightening. The screw operates by threading into a pre-tapped hole, securing components together under tension. Its application is widespread in mechanical assemblies where high torque and secure fastening are required ¹.

Purpose and Role in Truck Operation

In the context of heavy-duty trucks, the Twelve Point Cap Screw (Part #3648651) serves a specific purpose in securing critical components. It ensures that parts remain firmly attached under the demanding conditions encountered by heavy-duty trucks, such as vibrations, heavy loads, and varying temperatures. By providing a strong and reliable connection, it contributes to the structural integrity and safety of the vehicle ².

Key Features

The Twelve Point Cap Screw boasts several key features that enhance its performance and reliability. Its twelve-sided socket head allows for more contact points between the tool and the screw, facilitating more even torque application. The material composition typically includes high-strength steel, which offers excellent resistance to wear and corrosion. Additionally, the threading specifications are designed to provide a secure grip and prevent loosening over time ³.

Benefits

Using a Twelve Point Cap Screw offers several advantages. The design allows for increased torque application without the risk of cam-out, ensuring that components are tightened to the manufacturer’s specifications. This reduces the likelihood of stripping the screw head during installation or removal. Furthermore, the enhanced resistance to stripping and loosening contributes to the longevity and reliability of the fastening solution.

Installation Considerations

Proper installation of the Twelve Point Cap Screw is vital to ensure optimal performance and longevity. It is recommended to use the appropriate torque wrench to achieve the specified torque values, preventing over-tightening or under-tightening. Additionally, ensuring that the mating surfaces are clean and free of debris will enhance the screw’s grip and prevent premature loosening.

Troubleshooting and Maintenance

Common issues associated with Twelve Point Cap Screws include loosening due to vibrations or thermal expansion and contraction. Regular inspection and re-torquing can help maintain the integrity of the fastening. If a screw shows signs of damage or corrosion, it should be replaced to prevent failure. Proper lubrication during installation can also reduce the risk of seizing and facilitate easier removal in the future.

Compatibility and Applications

The Twelve Point Cap Screw is commonly used in various applications within heavy-duty trucks, including engine components, chassis assemblies, and body attachments. It is important to verify compatibility with other components to ensure a secure and reliable connection. Cummins provides detailed application guidelines to assist in selecting the appropriate fastener for specific uses.

Manufacturer Overview - Cummins

Cummins is a leading manufacturer in the automotive and heavy-duty truck industry, known for its commitment to quality and innovation. With a rich history of producing reliable and high-performance components, Cummins has established a reputation for excellence. Their dedication to research and development ensures that their products meet the rigorous demands of modern heavy-duty applications, providing customers with durable and efficient solutions ⁴.

Twelve Point Cap Screw 3648651 in Cummins Engines

The Twelve Point Cap Screw 3648651 is a critical component in various Cummins engine models, ensuring secure fastening and stability. This part is integral to the assembly and maintenance of several engine variants.

QSK45 CM500 and QSK60 CM500

In the QSK45 CM500 and QSK60 CM500 engines, the 3648651 screw is used in multiple applications, providing essential support and alignment for various engine components. Its twelve-point design allows for efficient torque application, enhancing the reliability of the fastening process.

QSK60 CM850 MCRS and QSK60 G CM2358 K110

For the QSK60 CM850 MCRS and QSK60 G CM2358 K110 engines, the 3648651 screw plays a vital role in maintaining the structural integrity of the engine. This screw is employed in areas where precise fastening is crucial, ensuring that components remain securely in place under operational stresses.

QSK60G

In the QSK60G engine, the 3648651 screw is utilized in key areas that require robust fastening solutions. Its design and material properties make it suitable for high-stress environments, contributing to the overall durability and performance of the engine.

QSK78 CM500

Similarly, in the QSK78 CM500 engine, the 3648651 screw is used in various applications to ensure that components are fastened securely. This screw’s twelve-point design facilitates easier and more efficient torque application, which is essential for maintaining the engine’s operational integrity.

Component Usage

The 3648651 Twelve Point Cap Screw is an essential component in various engine systems, providing secure and reliable fastening for multiple assemblies. Its application spans across different components, ensuring the integrity and functionality of the engine system.

Motor Assembly

In the motor assembly, the Twelve Point Cap Screw is utilized to fasten critical components such as the motor housing to the engine frame. This secure attachment ensures that the motor remains stable during operation, reducing vibrations and potential misalignments that could lead to performance issues or damage.

Starting System

Within the starting system, the Twelve Point Cap Screw plays a significant role in attaching the starter motor to the engine block. This secure connection is vital for the efficient transfer of torque from the starter motor to the flywheel, ensuring a smooth and reliable engine start. The screw’s design allows for easy installation and removal, facilitating maintenance and repairs.

Mounting Applications

The Twelve Point Cap Screw is also employed in various mounting applications throughout the engine system. It is used to mount ancillary components such as sensors, brackets, and auxiliary systems to the engine frame. This ensures that these components remain firmly in place, operating within their designed parameters and contributing to the overall efficiency and reliability of the engine.

Starting Motor Attachment

Specifically, in the starting motor attachment, the Twelve Point Cap Screw is crucial for securing the starting motor to its designated position on the engine. This attachment point must withstand significant forces during engine start-up, making the robust design of the Twelve Point Cap Screw ideal for this application. Its ability to provide a strong and durable connection helps maintain the starting motor’s alignment and functionality.

Integration with Starting Motor Components

Beyond the primary attachment, the Twelve Point Cap Screw is also used within the starting motor itself to secure internal components. This includes fastening gears, solenoids, and electrical connections, ensuring that all parts within the starting motor operate harmoniously. The screw’s design allows for precise torque application, which is essential for the accurate functioning of these intricate components.

Conclusion

In summary, the 3648651 Twelve Point Cap Screw is a versatile and reliable fastening solution across various engine components, contributing to the overall performance and durability of the engine system. Its design and material properties make it suitable for high-stress environments, ensuring secure and reliable fastening in critical applications.