3681268
Captive Washer Cap Screw
Cummins®

The 3681268 Captive Washer Cap Screw, manufactured by Cummins, is a specialized fastener designed for use in commercial truck maintenance and operation. Cummins, a well-established name in the commercial truck industry, produces a range of high-quality components that contribute to the reliability and efficiency of heavy-duty vehicles. This Cummins part plays a significant role in securing various parts within the truck’s mechanical systems.

Basic Concepts

A Captive Washer Cap Screw is a type of fastener that includes an integrated washer, which is held in place by a protrusion or step on the screw’s shank. This design ensures that the washer remains attached to the screw during installation, reducing the risk of loss and simplifying the fastening process. In mechanical assemblies, these screws are used to secure components together while providing a consistent and reliable clamping force ¹.

Purpose and Role in Truck Operation

In the context of commercial trucks, the 3681268 Captive Washer Cap Screw serves to secure components and maintain structural integrity. It is commonly used in applications where vibration and movement could cause standard fasteners to loosen over time. By providing a secure and stable connection, this screw helps to ensure that critical components remain in place, contributing to the overall safety and performance of the vehicle ².

Key Features

The 3681268 Captive Washer Cap Screw features a design that incorporates an integrated washer, which is held securely in place by a step on the screw’s shank. This screw is typically made from high-strength materials, such as alloy steel, to ensure durability and resistance to wear. The design includes a hex head for easy installation using standard tools, and the integrated washer helps to distribute clamping force evenly, reducing the risk of damage to connected components.

Benefits

Using the 3681268 Captive Washer Cap Screw offers several advantages. The integrated washer simplifies the installation process, as there is no need to handle separate washers that could be lost or misplaced. This design also ensures consistent clamping force, which contributes to improved reliability and reduced maintenance requirements. Additionally, the high-strength material used in the screw’s construction enhances its durability, making it suitable for demanding applications in commercial trucks ³.

Installation Process

To install the 3681268 Captive Washer Cap Screw, begin by ensuring that the mating surfaces are clean and free of debris. Position the screw so that the integrated washer is aligned with the hole in the component. Using a socket wrench or similar tool, turn the screw clockwise to secure the components together. It is important to apply the correct torque specification to ensure proper clamping force without over-tightening, which could damage the screw or connected components.

Common Applications

The 3681268 Captive Washer Cap Screw is commonly used in various mechanical systems within commercial trucks. Typical applications include securing engine components, transmission parts, and chassis elements. Its versatility and reliability make it a popular choice for a wide range of fastening tasks in heavy-duty vehicles.

Troubleshooting and Maintenance

To maintain the performance of the 3681268 Captive Washer Cap Screw, regular inspections should be conducted to ensure that the screw remains securely fastened and shows no signs of wear or damage. If loosening is detected, the screw should be re-tightened to the specified torque. In cases where significant wear or damage is observed, the screw should be replaced to prevent potential failure. Proper lubrication of moving parts can also help to reduce wear and extend the lifespan of the fastener.

Safety Considerations

When working with the 3681268 Captive Washer Cap Screw, it is important to observe several safety precautions. Ensure that the work area is clean and free of hazards. Use the correct tools and follow torque specifications to avoid over-tightening, which could lead to damage. Additionally, be mindful of environmental factors such as temperature and exposure to corrosive substances, as these can affect the performance and longevity of the screw.

Cummins 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 reputation for quality and reliability in the commercial truck industry. The company’s extensive product range includes engines, powertrain components, and aftermarket parts, all of which are designed to meet the demanding requirements of heavy-duty applications. The 3681268 Captive Washer Cap Screw is a testament to Cummins’ commitment to providing high-quality, reliable components for the commercial truck market.

Compatibility with Cummins Engines

The 3681268 Captive Washer Cap Screw is designed to fit a variety of Cummins engines. Below is a detailed breakdown of its compatibility across different engine models:

ISX Series Engines

• ISX CM570
• ISX CM870
• ISX CM871

The 3681268 is compatible with the ISX series engines, including the ISX CM570, ISX CM870, and ISX CM871. These engines are known for their robust performance and reliability, often used in heavy-duty applications.

ISX15 Series Engines

• ISX15 CM2250
• ISX15 CM2250 SN
• ISX15 CM2350 X101

For the ISX15 series, the 3681268 fits the ISX15 CM2250, ISX15 CM2250 SN, and ISX15 CM2350 X101 engines. These engines are designed to deliver high power output and efficiency, making them suitable for various industrial and commercial applications.

QSX15 Series Engines

• QSX15 CM2250
• QSX15 CM2250 ECF
• QSX15 CM2350 X105

The QSX15 series engines, including the QSX15 CM2250, QSX15 CM2250 ECF, and QSX15 CM2350 X105, also accommodate the 3681268. These engines are engineered for superior performance and are often used in demanding environments.

X15 Series Engine

• X15 CM2350 X116B

Lastly, the X15 CM2350 X116B engine is compatible with the 3681268. This engine is designed to provide exceptional power and efficiency, making it a reliable choice for various heavy-duty applications.

Role in Engine Systems

The 3681268 Captive Washer Cap Screw is integral in securing various components within engine systems, ensuring stability and proper function.

Cylinder Block

In the cylinder block, the 3681268 is used to fasten components such as cylinder head covers, oil pans, and other auxiliary parts. Its design ensures that these components remain securely attached, minimizing the risk of leaks and ensuring the structural integrity of the cylinder block. The captive washer feature prevents the screw from loosening over time, which is essential for maintaining consistent compression and sealing within the engine.

Front Gear Housing

Within the front gear housing, the 3681268 plays a significant role in attaching the housing to the engine frame or other supporting structures. This secure attachment is vital for the proper alignment and operation of the gears housed within. The screw’s captive washer ensures that vibrations and dynamic loads do not cause the screw to back out, which could lead to misalignment and subsequent gear failure.

By providing a reliable fastening solution, the 3681268 Captive Washer Cap Screw contributes to the overall durability and performance of the engine systems it is a part of.

Conclusion

The 3681268 Captive Washer Cap Screw is a critical component in the maintenance and operation of commercial trucks. Its design, featuring an integrated washer and high-strength material, ensures reliable and secure fastening in demanding applications. Proper installation, regular maintenance, and adherence to safety considerations are essential for maximizing the performance and longevity of this Cummins part.