5261711
Twelve Point Cap Screw
Cummins®

Introduction

The Twelve-Point Cap Screw Part #5261711, manufactured by Cummins, is a specialized fastener designed for use in commercial truck applications. Cummins, a well-established name in the commercial truck industry, produces this component to meet the demanding requirements of heavy-duty truck operations. This part is integral to ensuring the secure assembly of various truck components, contributing to the overall reliability and performance of commercial vehicles.

Basic Concepts of Twelve-Point Cap Screws

A twelve-point cap screw is a type of fastener characterized by its hexagonal head with six additional points, providing a larger contact area compared to traditional hex cap screws. This design allows for better torque application and reduced risk of cam-out during tightening ¹. Twelve-point cap screws are commonly used in mechanical assemblies where high torque and secure fastening are required. They are particularly favored in applications involving vibration or dynamic loads, as their design helps maintain a tighter hold.

Purpose and Role in Truck Operation

The 5261711 Twelve-Point Cap Screw 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 stable connection, this cap screw helps ensure that critical components remain firmly in place, even under the strenuous conditions encountered in commercial truck operations. Its application in these areas contributes to the overall durability and reliability of the truck.

Key Features

The 5261711 Twelve-Point Cap Screw features a robust design that includes a twelve-point head for enhanced torque application and reduced cam-out. It is constructed from high-strength materials, typically alloy steel, to withstand the rigors of heavy-duty use. The screw’s threaded section is precision-machined to ensure a tight and secure fit within the mating components. Additionally, it may include features such as a corrosion-resistant coating to enhance its durability in various operating environments.

Benefits

Using the 5261711 Twelve-Point Cap Screw in truck maintenance and repair offers several benefits. Its design allows for improved torque application, ensuring that components are securely fastened. The reduced risk of cam-out during tightening minimizes the potential for damage to the fastener or surrounding parts. Furthermore, the high-strength material and corrosion-resistant properties contribute to the screw’s longevity, making it a reliable choice for commercial truck applications.

Installation Guidelines

Proper installation of the 5261711 Twelve-Point Cap Screw is crucial to ensure secure fastening and optimal performance. Follow these guidelines for installation:

1. Ensure the mating threads are clean and free of debris.
2. Align the cap screw with the designated hole and begin threading by hand to avoid cross-threading.
3. Use a torque wrench to tighten the cap screw to the specified torque value, which can be found in the truck’s service manual or on the packaging.
4. Double-check the tightness to confirm that the component is securely fastened.

Troubleshooting and Maintenance

Common issues with twelve-point cap screws include loosening due to vibration or dynamic loads, and corrosion in harsh environments. To troubleshoot these issues:

• Inspect the cap screw regularly for signs of loosening or corrosion.
• Re-tighten the screw if necessary, ensuring it is torqued to the specified value.
• Apply a thread locker or anti-seize compound to prevent loosening and corrosion, as recommended by the manufacturer.

Cummins: Manufacturer Overview

Cummins Inc. is a global power leader that designs, manufactures, and distributes engines, filtration, and power generation products. With a history spanning over a century, Cummins has established a strong reputation in the commercial truck industry for producing high-quality, reliable components. Their extensive product range includes engines, powertrains, and aftermarket parts, all designed to meet the demanding needs of commercial truck operators. Cummins’ commitment to innovation and quality makes them a trusted source for truck components, including the 5261711 Twelve-Point Cap Screw ².

Twelve-Point Cap Screw 5261711 in Cummins Engines

The Twelve-Point Cap Screw 5261711, manufactured by Cummins, is a critical component in various Cummins engine models. This screw is designed to provide robust fastening capabilities, ensuring secure connections in high-stress environments typical of engine assemblies. Below is a detailed overview of how this part integrates with different Cummins engines.

6C8.3, G8.3, and GTA8.3 CM558 Engines

The 6C8.3, G8.3, and GTA8.3 CM558 engines utilize the 5261711 cap screw in several key areas. These engines, known for their reliability and performance, require precise fastening to maintain structural integrity and operational efficiency. The screw is often used in securing components such as engine mounts, brackets, and various internal parts that need to withstand significant mechanical stress.

ISC CM2150, ISC CM554, ISC CM850, and ISC8.3 CM2250 Engines

In the ISC CM2150, ISC CM554, ISC CM850, and ISC8.3 CM2250 engines, the 5261711 cap screw is integral to the assembly of the engine’s internal and external components. These engines, part of the ISC series, are designed for heavy-duty applications and benefit from the enhanced durability and strength provided by this screw. It is commonly used in fastening the engine block, cylinder heads, and other critical assemblies.

ISL CM2150, ISL CM554, ISL G CM2180, ISL9 CM2150 SN, ISL9 CM2250, and ISL9.5 CM2880 L138 Engines

The ISL series engines, including the ISL CM2150, ISL CM554, ISL G CM2180, ISL9 CM2150 SN, ISL9 CM2250, and ISL9.5 CM2880 L138, also incorporate the 5261711 cap screw in their construction. These engines are known for their versatility and are used in a wide range of applications, from construction to agricultural machinery. The screw is essential in securing the engine’s main components, ensuring that the engine operates smoothly and reliably under various conditions.

L GAS PLUS CM556, L8.9, L8.9 CM2670 L134C, L8.9 L121, L8.9G CMOH2.0 L125B, L9 CM2670 L128B, L9.3 L105, and L9.5 L117 Engines

The 5261711 cap screw is also a vital component in the L series engines, such as the L GAS PLUS CM556, L8.9, L8.9 CM2670 L134C, L8.9 L121, L8.9G CMOH2.0 L125B, L9 CM2670 L128B, L9.3 L105, and L9.5 L117. These engines are designed for specific applications, including gas and diesel variants. The screw is used in fastening various parts, including the engine block, cylinder heads, and other structural components, ensuring the engine’s longevity and performance.

QSC8.3 CM2880 C102 and QSC8.3 CM554 Engines

The QSC8.3 CM2880 C102 and QSC8.3 CM554 engines also rely on the 5261711 cap screw for their assembly. These engines are known for their efficiency and power, and the screw plays a crucial role in maintaining the structural integrity of the engine. It is used in securing various components, ensuring that the engine operates reliably and efficiently.

Role of Part 5261711 Twelve-Point Cap Screw in Engine Systems

In the intricate assembly of engine systems, the part 5261711 Twelve-Point Cap Screw serves as a fundamental fastening element, ensuring the secure attachment of various components. Its application is widespread across different engine parts, contributing to the overall stability and functionality of the engine.

Cover Assembly

The Twelve-Point Cap Screw is instrumental in the secure attachment of the engine cover. This screw ensures that the cover remains firmly in place, protecting internal components from external contaminants and providing a streamlined exterior for the engine. The twelve-point design allows for enhanced torque application, reducing the risk of cam-out and ensuring a tight seal.

Front Gear Attachment

In the front gear assembly, the Twelve-Point Cap Screw plays a significant role in maintaining the precise alignment and secure fastening of the gear to its housing. This is essential for the smooth operation of the gear, as any misalignment or looseness could lead to increased wear, noise, and potential failure. The screw’s design facilitates easy and efficient tightening, which is vital during both initial assembly and maintenance procedures.

Mounting Applications

For mounting purposes, the Twelve-Point Cap Screw is often used to attach various engine components to the engine block or frame. This includes securing brackets, plates, and other structural elements that are critical for the engine’s operational integrity. The screw’s robust design ensures that these components remain fixed under the dynamic loads and vibrations experienced during engine operation.

Gear Cover Fastening

The gear cover, which encloses the gear train and related components, relies on the Twelve-Point Cap Screw for secure attachment. This is particularly important in maintaining the integrity of the lubrication system, as the gear cover often forms a part of the oil containment system. A well-fastened gear cover prevents oil leaks and ensures that the lubrication system functions effectively, contributing to the longevity and performance of the engine.

Conclusion

The 5261711 Twelve-Point Cap Screw is a versatile and reliable fastening solution in engine systems, playing a key role in the secure attachment of covers, gears, mountings, and gear covers. Its design and functionality are tailored to meet the demanding requirements of engine environments, ensuring both stability and efficiency in engine operations. The use of this part across various Cummins engines underscores its importance in ensuring the engines’ durability, reliability, and performance ³.