3278448
Twelve Point Cap Screw
Cummins®

The Twelve Point Cap Screw, identified by part number 3278448 and manufactured by Cummins, is a specialized fastener designed for use in commercial trucks. This component is integral to the structural integrity and operational efficiency of heavy-duty vehicles. Cummins, a renowned name in the commercial truck industry, ensures that this part meets stringent quality and performance standards ¹.

Basic Concepts of Twelve Point Cap Screws

A Twelve Point Cap Screw is a type of fastener characterized by its hexagonal socket head, which provides a larger contact area compared to traditional hex-head screws. This design reduces the risk of cam-out and stripping during installation and removal. In the automotive industry, Twelve Point Cap Screws are commonly used in applications requiring high torque and resistance to loosening, such as in engine components, chassis assemblies, and other critical areas where secure fastening is paramount ².

Role of the 3278448 Twelve Point Cap Screw in Truck Operation

The 3278448 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 frames. Its design ensures a secure and stable connection, which is vital for the safe and efficient operation of heavy-duty vehicles. The screw’s ability to withstand high torque and resist loosening under dynamic conditions makes it an ideal choice for these applications ³.

Key Features of the 3278448 Twelve Point Cap Screw

The 3278448 Twelve Point Cap Screw is engineered with several key features that enhance its performance. It is manufactured from high-strength alloy steel, providing excellent durability and resistance to wear. The screw features a fine thread, which allows for precise adjustments and secure fastening. Additionally, the twelve-point design offers increased torque capacity and reduces the likelihood of stripping during installation ⁴.

Benefits of Using the 3278448 Twelve Point Cap Screw

The use of the 3278448 Twelve Point Cap Screw offers several advantages. Its high torque capacity ensures a strong and reliable connection, while its resistance to stripping simplifies installation and removal. The screw’s durability in harsh operating conditions makes it suitable for use in commercial trucks, where components are subjected to significant stress and vibration. Furthermore, the twelve-point design provides a more secure fit compared to traditional hex-head screws, reducing the risk of loosening over time ⁵.

Installation and Usage Guidelines

Proper installation of the 3278448 Twelve Point Cap Screw is crucial for optimal performance. It is recommended to use a torque wrench to achieve the specified torque settings, ensuring a secure and consistent fastening. The screw should be installed in a clean, dry environment to prevent corrosion and ensure a strong bond. It is also important to follow the manufacturer’s guidelines for thread engagement and clearance to avoid damage to the screw or the mating component ⁶.

Troubleshooting Common Issues

Common issues associated with Twelve Point Cap Screws include loosening and corrosion. To address loosening, it is important to ensure that the screw is properly torqued during installation and that the mating surfaces are clean and free of debris. Regular inspection and re-torquing may be necessary to maintain a secure connection. Corrosion can be mitigated by applying a suitable anti-corrosion coating or lubricant during installation and by conducting routine inspections to identify and address any signs of rust or degradation ⁷.

Maintenance Tips

To prolong the lifespan of the 3278448 Twelve Point Cap Screw, routine maintenance practices should be followed. Regular inspections should be conducted to check for signs of wear, corrosion, or loosening. Any damaged or corroded screws should be replaced promptly to maintain the integrity of the fastening. Additionally, ensuring that all mating surfaces are clean and free of debris will help prevent issues and ensure a strong, secure connection ⁸.

Cummins: A Brief Overview

Cummins Inc. is a global power leader that designs, manufactures, and distributes engines, filtration, and power generation products. With a rich history spanning over a century, Cummins has established a strong reputation in the commercial truck industry for producing high-quality, reliable components. The company’s extensive product range includes engines, powertrains, and aftermarket parts, all designed to meet the demanding requirements of heavy-duty applications. Cummins’ commitment to innovation and excellence ensures that its products, including the 3278448 Twelve Point Cap Screw, deliver superior performance and durability ⁹.

Twelve Point Cap Screw 3278448 in Cummins Engines

The Twelve Point Cap Screw 3278448, manufactured by Cummins, is a critical component in various Cummins engine models. This screw is designed to provide robust fastening in high-stress environments, ensuring the integrity and reliability of engine assemblies. Below is a detailed look at how this screw fits into different Cummins engines.

Common Engine Families

4B3.9, 6B5.9, 6C8.3, B3.3, B4.5 CM2350 B129B, B5.6 CM2670 B152B, B5.9 G, B5.9 GAS PLUS CM556, B6.7 CM2350 B135B, B6.7 CM2670 B153B, C GAS PLUS CM556, C8.3 G, D4.0 CM2620 D103B, F3.8 CM2350 F120B, F3.8 CM2350 F128C, F3.8 CM2620 F137B, F4.5 CM2620 F139B

In these engines, the Twelve Point Cap Screw 3278448 is utilized in various applications, including securing engine blocks, cylinder heads, and other critical components. The screw’s twelve-point design ensures a secure grip, reducing the risk of rounding off and providing reliable fastening.

ISB CM550, ISB/ISD4.5 CM2150 B119, ISB/ISD6.7 CM2150 SN, ISB4.5 CM2350 B104, ISB5.9 CM2880 B110, ISB5.9 CM2880 B140, ISB5.9 CM2880 B149, ISB5.9G CM2180

For the ISB series engines, the Twelve Point Cap Screw 3278448 plays a vital role in maintaining the structural integrity of the engine. These engines, known for their durability and performance, rely on this screw for fastening various parts, including the engine block, cylinder heads, and other critical assemblies. The screw’s design ensures that it can withstand the high torque and stress levels typical in these engines ¹⁰.

Specific Applications

• Engine Blocks and Cylinder Heads: The screw is often used to secure the engine block and cylinder heads, ensuring that these components remain tightly fastened under all operating conditions.
• Turbocharger Mounting: In turbocharged engines, the Twelve Point Cap Screw 3278448 is used to mount the turbocharger, ensuring it remains securely in place and functions optimally.
• Exhaust Manifolds: This screw is also used in the assembly of exhaust manifolds, providing a reliable fastening solution that can endure high temperatures and pressures.

The Twelve Point Cap Screw 3278448 is a testament to Cummins’ commitment to quality and reliability. Its use across various engine models underscores its versatility and importance in maintaining the structural integrity and performance of Cummins engines ¹¹.

Part 3278448 Twelve Point Cap Screw Component Usage

In the intricate assembly of engine systems, the part 3278448 Twelve Point Cap Screw is instrumental in ensuring the secure fastening of various components. Its application spans across multiple engine elements, contributing to the overall stability and functionality of the system.

Auxiliary Pump and Compressor

The Twelve Point Cap Screw is utilized in the assembly of the auxiliary pump and compressor. It secures the pump housing to the engine block, ensuring a tight seal that prevents leaks and maintains the efficiency of the pump. Similarly, in the compressor, it fastens the housing to the mounting bracket, which is essential for the compressor’s operation in pressurizing the air system.

Flywheel and Mounting

In the flywheel assembly, the Twelve Point Cap Screw plays a role in attaching the flywheel to the crankshaft. This connection is vital for the smooth transfer of power from the engine to the transmission. Additionally, it is used in the mounting of the flywheel to the engine block, ensuring that it remains securely in place during operation.

Alternator and Mounting

The alternator, which is responsible for generating electrical power in the engine, relies on the Twelve Point Cap Screw for its secure attachment to the engine block. This screw is also used in the mounting of the alternator to its bracket, ensuring that it remains stable and aligned with the crankshaft pulley.

Twin Alternator Mounting Kit

In systems equipped with a twin alternator setup, the Twelve Point Cap Screw is employed in the mounting kit to secure both alternators to the engine block. This ensures that both alternators operate efficiently and in sync, providing the necessary electrical power for the engine’s components.

General Application

Across these applications, the Twelve Point Cap Screw’s design allows for a more secure and vibration-resistant connection compared to standard hex cap screws. Its use in these critical engine components underscores its importance in maintaining the integrity and performance of the engine system ¹².

Conclusion

The 3278448 Twelve Point Cap Screw is a critical component in the operation and maintenance of commercial trucks and Cummins engines. Its design, featuring a twelve-point head and high-strength alloy steel construction, ensures secure fastening, high torque capacity, and resistance to loosening and corrosion. Proper installation, regular maintenance, and adherence to manufacturer guidelines are essential for maximizing the performance and longevity of this part. Cummins’ commitment to quality and reliability is evident in the design and application of this screw, making it a vital element in the structural integrity and performance of heavy-duty vehicles and engines ¹³.