3251789
Hexagon Head Cap Screw
Cummins®

Introduction

The Cummins 3251789 Hexagon Head Cap Screw is a specialized fastener designed for heavy-duty truck applications. Its purpose is to securely join various components within the truck, ensuring structural integrity and reliable performance under demanding conditions. The significance of this screw lies in its ability to withstand high stress and environmental factors commonly encountered in heavy-duty trucking ¹.

Basic Concepts of Hexagon Head Cap Screws

A Hexagon Head Cap Screw is a type of fastener characterized by its hexagonal head, which allows for efficient tightening and loosening using a wrench or socket. The screw’s design includes external threads that engage with internal threads in a mating part, creating a secure connection. In fastening applications, these screws are commonly used for their strength and ease of use ².

Role of the 3251789 Hexagon Head Cap Screw in Truck Operation

This Cummins part plays a role in the operation and maintenance of heavy-duty trucks by securing critical components. It is utilized in various applications, including engine mounts, chassis assemblies, and other structural elements. Proper installation and maintenance of these screws are vital for ensuring the truck’s overall performance and safety ¹.

Key Features

The Cummins 3251789 Hexagon Head Cap Screw features a robust material composition, typically consisting of high-grade steel, which provides excellent strength and durability. It has a specific thread type designed for optimal engagement and load distribution. The head design is hexagonal, facilitating easy and precise tightening with the appropriate tools.

Benefits of Using the 3251789 Hexagon Head Cap Screw

Utilizing this Cummins part offers several advantages. Its durable material composition ensures long-lasting performance even under strenuous conditions. The screw’s design provides resistance to corrosion, enhancing its reliability in various environments. Additionally, the hexagonal head allows for straightforward installation and adjustment, contributing to efficient maintenance procedures ².

Installation Guidelines

To install the Cummins 3251789 Hexagon Head Cap Screw, begin by ensuring the mating threads are clean and free of debris. Use a torque wrench to tighten the screw to the specified torque setting, which ensures proper engagement without over-tightening. Recommended tools include a socket wrench compatible with the screw’s head size and a torque wrench for accurate tightening.

Maintenance Tips

Maintaining this Cummins part involves periodic inspection to check for signs of wear, corrosion, or loosening. Regular tightening may be necessary to ensure the screw remains securely fastened. Additionally, protecting the screw from environmental factors such as moisture and chemicals can prolong its service life ³.

Troubleshooting Common Issues

Common issues with the Cummins 3251789 Hexagon Head Cap Screw may include loosening over time, corrosion due to exposure to harsh elements, or damage from excessive force during installation. To address these problems, inspect the screw regularly, reapply torque as needed, and consider protective coatings or replacements if corrosion or damage is detected.

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 is renowned for its innovative solutions and commitment to quality. The company’s extensive product offerings cater to various industries, including automotive, construction, and power generation, solidifying its reputation as a trusted provider of reliable and high-performance components.

Hexagon Head Cap Screw 3251789 in Cummins Engines

The Hexagon Head Cap Screw part number 3251789, manufactured by Cummins, is a critical component in various Cummins engine models. This screw is integral to the assembly and maintenance of these engines, ensuring secure fastening and structural integrity.

6C8.3 and C8.3 G Engines

The 6C8.3 and C8.3 G engines utilize the 3251789 screw in several key areas. These include securing engine components, such as cylinder heads, to the engine block, ensuring that all parts remain tightly fastened under operational stresses.

G8.3 and G8.3 CM558 Engines

In the G8.3 and G8.3 CM558 engines, the 3251789 screw is used extensively in the assembly of the engine’s internal and external components. Its application ranges from fastening the engine block to other critical assemblies, ensuring that the engine operates smoothly and efficiently.

GTA8.3 CM558 and ISC CM554 Engines

For the GTA8.3 CM558 and ISC CM554 engines, the 3251789 screw is employed in both the internal and external structural assemblies. This includes securing various engine mounts and brackets, which are crucial for maintaining the engine’s alignment and stability.

ISC CM850 and ISL9 CM2150 SN Engines

In the ISC CM850 and ISL9 CM2150 SN engines, the 3251789 screw is used in the assembly of larger structural components. These engines benefit from the screw’s strength and reliability, ensuring that all parts remain securely fastened during operation.

QSK45 CM500 and QSK60 CM500 Engines

The QSK45 CM500 and QSK60 CM500 engines also incorporate the 3251789 screw in their assembly. This screw is used to secure various engine components, including those that are subject to high stress and vibration, ensuring the engine’s longevity and performance.

QSL9 G CM558 and QST30 CM552 Engines

Finally, the QSL9 G CM558 and QST30 CM552 engines utilize the 3251789 screw in the assembly of their structural components. This includes securing parts that are critical to the engine’s operation, ensuring that the engine maintains its structural integrity under all operating conditions.

Role of Part 3251789 Hexagon Head Cap Screw in Engine Systems

The part 3251789 Hexagon Head Cap Screw is integral to the assembly and functionality of various engine components. Its primary role is to secure and maintain the structural integrity of these components, ensuring optimal performance and safety.

Cleaner and Air Coupling

In the air cleaner system, the Hexagon Head Cap Screw is used to fasten the air cleaner housing to the engine or chassis. This secure attachment ensures that the air intake system remains sealed, preventing unfiltered air from entering the engine and maintaining efficient air filtration.

For the air coupling, the screw is essential in connecting the air intake hose to the throttle body or intake manifold. This connection must be tight to prevent air leaks, which can affect engine performance and fuel efficiency.

Fuel Pump and Flexplate

In the fuel system, the Hexagon Head Cap Screw is utilized to secure the fuel pump to the fuel tank or the engine block. This ensures that the fuel pump remains stable and operates efficiently, providing consistent fuel delivery to the engine.

When it comes to the flexplate, the screw plays a role in attaching the flexplate to the crankshaft. This connection is vital for transmitting power from the engine to the transmission, ensuring smooth operation of the drivetrain.

Flywheel and Plumbing

The flywheel assembly often requires the Hexagon Head Cap Screw to secure the flywheel to the crankshaft. This attachment is essential for maintaining the balance and smooth operation of the engine, especially during the power transmission phase.

In plumbing applications within the engine system, such as the charge air bypass and radiator connections, the screw ensures that hoses and fittings are securely attached. This prevents leaks and maintains the integrity of the cooling and charge air systems, which are vital for engine temperature regulation and performance.

Rail, Base, and Support

The rail, base, and support structures of the engine often utilize the Hexagon Head Cap Screw to ensure these components are firmly attached to the engine block or chassis. This stability is important for the overall structural integrity of the engine, especially under varying operating conditions.

Rear Engine Components

For rear engine components, such as the rear engine mount or support brackets, the Hexagon Head Cap Screw is used to secure these parts to the chassis or engine block. This ensures that the engine remains properly aligned and supported, reducing vibrations and enhancing overall engine performance.

Conclusion

The Cummins 3251789 Hexagon Head Cap Screw is a vital component in the assembly and maintenance of heavy-duty trucks and Cummins engines. Its robust design, ease of installation, and resistance to corrosion make it an essential part for ensuring the structural integrity and reliable performance of various engine components. Proper installation, maintenance, and troubleshooting are crucial for maximizing the lifespan and efficiency of this part.