3920691
Retaining Ring
Cummins®

Introduction

The Cummins 3920691 Retaining Ring is a component designed for use in commercial trucks. Its purpose is to secure various parts within the truck’s mechanical systems, ensuring they remain in place under operational conditions. This retaining ring is specifically engineered to meet the demands of heavy-duty applications, contributing to the overall reliability and performance of the vehicle ¹.

Basic Concepts of Retaining Rings

Retaining rings, also known as circlips, are mechanical fasteners used to prevent components from moving along a shaft or within a housing. They operate by exerting a constant pressure against the inner diameter of a bore or the outer diameter of a shaft, securing parts in place without the need for additional fasteners. This design allows for easy installation and removal, making them a popular choice in various mechanical systems ².

Role of the 3920691 Retaining Ring in Truck Operation

The Cummins 3920691 Retaining Ring plays a specific role in the operation of a truck by securing components within the engine and transmission systems. It is typically placed in grooves machined into shafts or housings, where it prevents parts such as gears, bearings, and seals from shifting during operation. This securement is vital for maintaining the precise alignment and operation of these components, directly influencing the truck’s performance and durability ³.

Key Features

The Cummins 3920691 Retaining Ring is characterized by several key features that enhance its performance and durability. It is made from high-quality materials, often steel or stainless steel, which provide the necessary strength and corrosion resistance for heavy-duty applications. The design of the ring includes a coiled shape that allows it to flex during installation and removal, yet maintain a firm grip on the components it secures. Additionally, the ring’s surface may be treated to improve wear resistance and reduce the risk of galling ⁴.

Benefits

The use of the Cummins 3920691 Retaining Ring offers several benefits to the operation of commercial trucks. By securely holding components in place, it contributes to improved reliability and performance of the truck’s mechanical systems. This securement reduces the likelihood of component misalignment or failure, which can lead to increased efficiency and reduced maintenance costs. Furthermore, the design of the retaining ring allows for quick and easy installation and removal, facilitating maintenance procedures ⁵.

Troubleshooting and Maintenance

Common issues associated with retaining rings include deformation, corrosion, and improper installation. To troubleshoot problems, it is important to inspect the ring for signs of wear or damage and ensure it is correctly seated in the groove. Maintenance practices for the Cummins 3920691 Retaining Ring include regular inspection during routine maintenance checks and replacement if any signs of wear or damage are detected. Proper installation techniques should be followed to ensure the ring functions as intended ⁶.

Cummins Engine Compatibility with Retaining Ring Part 3920691

The Cummins Retaining Ring part number 3920691 is designed to fit seamlessly with a variety of Cummins engines. This part ensures the proper functioning of the engine by maintaining the alignment and stability of various internal components. Below is a detailed overview of the engines that are compatible with this retaining ring.

Compatible Engines

• 4B3.9, 6B5.9, B3.3, B4.5 CM2350 B129B, B4.5 RGT, B5.6 CM2670 B152B, B5.9 CM2670 B166C, B5.9 G, B5.9 GAS PLUS CM556
• B6.7 CM2350 B135B, B6.7 CM2670 B153B, B6.7 CM2670 B164C, B6.7 G CMOH6.0 B125
• D4.0 CM2620 D103B, F3.8 CM2350 F120B, F3.8 CM2350 F128C, F3.8 CM2620 F137B, F3.8 F102, F4.5 CM2620 F139B, F4.5 CM2620 F141C
• G5.9, G5.9 CM558, ISB (Chrysler), ISB CM2150, ISB CM550

These engines require the retaining ring part 3920691 to maintain the integrity of the engine’s internal components, ensuring smooth operation and longevity ⁷.

Role of Part 3920691 Retaining Ring in Engine Systems

The Part 3920691 Retaining Ring is an essential component in various engine systems, ensuring the secure placement and operation of multiple parts.

• Block 6-B Short: The retaining ring holds components such as the camshaft and connecting rod and piston assemblies in place within the cylinder block kit.
• Short 4BT, Short 6-BT, Short 6BT, Short E2 Incent blocks: It secures the engine piston 1.0 MMO/S kit and engine piston (0.5 oversized) kit within the block.
• Short E3 Incent block: The retaining ring is crucial for the installation of the engine piston (1 oversized) kit.
• Engine Piston 1.0mm Kit and Piston 0.50 mm O/S: The retaining ring secures these components within the cylinder block kit.
• Long Block and Long Block Kit: It holds the piston engine kit and piston ring kit in place.
• Performance Part and Performance Parts applications: Ensures high-performance components are securely fitted within the cylinder block kit.
• Seal Kit and Set, Eng PST (STD. 210HP): Ensures these components are correctly installed and maintained within the engine block.
• Short 6B Block and Short Block Kit: Secures various components, including the onboard spares kit ⁸.

Conclusion

The Cummins 3920691 Retaining Ring is a vital component in the operation and maintenance of commercial trucks and various Cummins engines. Its design and features contribute to the reliability, performance, and durability of the mechanical systems it supports. Regular maintenance and proper installation are essential to ensure the retaining ring functions as intended, ultimately leading to increased efficiency and reduced maintenance costs.