3012478
Captive Washer Cap Screw
Cummins®

The 3012478 Captive Washer Cap Screw by Cummins is a specialized fastener designed for heavy-duty truck applications. This component plays a role in ensuring the integrity and functionality of truck assemblies by providing secure and reliable fastening solutions. Its design and construction are tailored to meet the demanding requirements of heavy-duty environments, contributing to the overall performance and durability of truck components ¹.

Basic Concepts of Captive Washer Cap Screws

Captive washer cap screws are a type of fastener that includes an integrated washer, which remains attached to the screw throughout its use. This design differs from standard cap screws, which require separate washers that can sometimes become misplaced or lost during installation. The integrated washer in captive washer cap screws plays a role in providing a uniform distribution of clamping force, which helps to prevent damage to the fastened materials and ensures a more consistent and secure connection ².

Purpose and Function of 3012478 Captive Washer Cap Screw

The 3012478 Captive Washer Cap Screw is designed to play a specific role in truck operations by securely fastening various components. It contributes to the stability and reliability of truck assemblies by ensuring that parts remain firmly in place under varying loads and conditions. Common applications within truck assemblies include fastening engine components, chassis parts, and other critical systems where secure and durable connections are required.

Key Features

The 3012478 Captive Washer Cap Screw features several key attributes that enhance its performance and durability. These include a robust material composition, typically high-strength steel, which provides the necessary tensile strength and resistance to corrosion. The screw also features a specific thread type that ensures a tight and secure fit, along with unique design elements such as the integrated washer, which plays a role in distributing clamping force evenly across the fastened materials.

Benefits of Using Captive Washer Cap Screws

Using captive washer cap screws offers several advantages in truck applications. These fasteners provide improved load distribution, which helps to prevent localized stress and potential failure of the fastened components. The integrated washer reduces the risk of washer loss during installation, ensuring that the fastening system remains complete and effective. Additionally, the secure connection provided by captive washer cap screws enhances the overall reliability and performance of truck assemblies.

Installation Guidelines

Proper installation of the 3012478 Captive Washer Cap Screw is important for ensuring optimal performance and longevity. Step-by-step instructions for installation include selecting the appropriate drill size for the pilot hole, ensuring the screw is aligned correctly with the fastening points, and using a torque wrench to achieve the recommended tightening torque. Best practices involve checking for proper alignment and ensuring that the integrated washer is seated correctly to distribute clamping force effectively.

Troubleshooting and Maintenance

Common issues associated with captive washer cap screws can include loosening over time due to vibration or varying loads, corrosion in harsh environments, and wear from repeated use. Maintenance tips to prolong the life of the screw include regular inspection for signs of wear or corrosion, re-torquing fasteners as needed, and replacing screws that show signs of significant wear or failure. Identifying these signs early can help prevent more serious issues and ensure the continued reliability of truck components.

Compatibility and Applications

The 3012478 Captive Washer Cap Screw is typically used within Cummins engines and other truck components where secure and durable fastening is required. Its design ensures compatibility with various materials and environments, making it a versatile choice for a range of heavy-duty applications.

Cummins: A Brief Overview

Cummins Inc. is a leading manufacturer in the automotive industry, known for its history of innovation and commitment to quality. The company offers a wide range of products designed for heavy-duty applications, including engines, powertrains, and components like the 3012478 Captive Washer Cap Screw. Cummins’ focus on reliability and performance makes it a trusted provider of components for the heavy-duty truck industry.

Cummins Part 3012478 Captive Washer Cap Screw Compatibility

The Cummins part 3012478 Captive Washer Cap Screw is a versatile component designed to fit a variety of Cummins engines. This part is essential for securing various engine components, ensuring the integrity and performance of the engine.

Engine Compatibility

4B3.9 and 6B5.9 Series

The 4B3.9 and 6B5.9 engines are part of Cummins’ mid-range diesel engines, often used in agricultural and industrial applications. The Captive Washer Cap Screw is used in these engines to secure components such as valve covers, oil pans, and other critical parts.

G855 and G855 CM558

The G855 and G855 CM558 engines are part of Cummins’ heavy-duty diesel lineup, typically used in construction and mining equipment. The Captive Washer Cap Screw is utilized in these engines for securing heavy-duty components, ensuring they remain tightly fastened under high stress and load conditions.

GTA855 CM558 (CM2358) G101

This engine is a high-output variant of the G855 series, often used in large construction and mining equipment. The Captive Washer Cap Screw is critical in maintaining the structural integrity of the engine by securing various high-stress components.

K19, K38, and K50 Series

The K19, K38, and K50 series engines are Cummins’ medium-duty diesel engines, commonly used in various industrial applications. The Captive Washer Cap Screw is used to secure components such as the engine block, cylinder heads, and other critical parts.

KTA19GC and KTA19GC CM558

These engines are part of Cummins’ heavy-duty diesel lineup, often used in power generation and marine applications. The Captive Washer Cap Screw is essential for securing components in these high-output engines, ensuring they remain tightly fastened under demanding conditions.

N14 G and N14 MECHANICAL

The N14 G and N14 MECHANICAL engines are part of Cummins’ heavy-duty diesel lineup, commonly used in on-highway and off-highway applications. The Captive Washer Cap Screw is used to secure various components, including the engine block and cylinder heads.

NH/NT 855

The NH/NT 855 engines are part of Cummins’ heavy-duty diesel lineup, often used in construction and mining equipment. The Captive Washer Cap Screw is used to secure components in these high-output engines, ensuring they remain tightly fastened under demanding conditions.

QSK19 Series

The QSK19 series engines, including variants like QSK19 CM2350 K105, QSK19 CM2350 K114, QSK19 CM2350 K144G, QSK19 CM500, QSK19 CM850 MCRS, and QSK19G, are part of Cummins’ heavy-duty diesel lineup, commonly used in power generation and marine applications. The Captive Washer Cap Screw is essential for securing components in these high-output engines, ensuring they remain tightly fastened under demanding conditions.

V28 and V903

The V28 and V903 engines are part of Cummins’ heavy-duty diesel lineup, often used in power generation and marine applications. The Captive Washer Cap Screw is used to secure components in these high-output engines, ensuring they remain tightly fastened under demanding conditions.

Role of Part 3012478 Captive Washer Cap Screw in Engine Systems

The Part 3012478 Captive Washer Cap Screw is integral to the assembly and secure functioning of various engine components. Its application spans across multiple systems, ensuring stability, alignment, and efficient operation.

In the adapter connection system, this screw plays a role in securing the adapter to the engine block, ensuring a leak-free and stable connection. For the air compressor support, it helps in maintaining the structural integrity by fastening the support brackets, which are essential for the compressor’s operation.

When it comes to the auxiliary pump mounting, the screw is used to attach the pump securely to the engine, preventing any movement that could affect the pump’s performance. In the base parts less rgt assembly, it ensures that the base components are firmly attached, providing a stable foundation for other engine parts.

For the drive accessory, the screw is employed to secure accessories to the engine, ensuring they operate smoothly without any undue stress or movement. In the engine cast cooler and engine oil cooler systems, it is used to fasten the coolers to the engine, maintaining efficient cooling by ensuring a tight fit.

In the engine mounting system, the screw is vital for securing the engine to the vehicle’s frame, providing stability and reducing vibrations. For the fan drive array, it ensures that the fan components are securely attached, allowing for efficient air circulation and cooling.

The filter and cooler assembly also benefits from this screw, as it secures the filter and cooler components, ensuring they remain in place and function correctly. In the fuel tube mounting system, it is used to attach the fuel tubes securely, preventing leaks and ensuring a consistent fuel supply.

For the gear housing mounting cover, the screw ensures that the cover is securely attached to the gear housing, protecting the internal components. In the heat exchanger system, it is used to fasten the exchanger to the engine, ensuring efficient heat transfer.

The lubricating oil cooler and lubricating oil suction connection systems also utilize this screw to secure the components, ensuring efficient lubrication and oil flow. In the oil cooler cover and oil filter and cooler assemblies, it is used to attach the covers and filters securely, maintaining the integrity of the cooling and filtration systems.

For the oil pan/noise panel mtg., the screw is essential for securing the oil pan and noise panel, ensuring they remain in place and function correctly. In the rear bearing and cover support, it helps in securing the bearing and cover, ensuring smooth operation of the rear components.

The resistor, corrosion diag system uses this screw to attach the resistor securely, ensuring accurate diagnosis and protection against corrosion. In the support and bushing assembly, it is used to fasten the support and bushing components, providing stability and reducing wear.

For the torque converter, the screw is employed to secure the converter to the engine, ensuring efficient power transfer. In the water mounting pump and water outlet connection systems, it is used to attach the pump and connection securely, ensuring efficient water flow and cooling.

Finally, in the water pump mounting support, the screw is vital for securing the water pump, ensuring it operates efficiently and remains in place.

Conclusion

The 3012478 Captive Washer Cap Screw by Cummins is a critical component in heavy-duty truck applications, providing secure and reliable fastening solutions. Its design and features ensure compatibility with various engine components, enhancing the stability, alignment, and efficient operation of truck assemblies. Proper installation and maintenance of this part are essential for ensuring the longevity and reliability of truck components.