3928865
Fan Clutch
Cummins®

Introduction

The Cummins 3928865 Fan Clutch is a component designed for use in the engine cooling systems of commercial trucks. Its purpose is to regulate the airflow directed to the radiator, which is crucial for maintaining optimal engine temperature. By adjusting the fan speed in response to engine temperature, the fan clutch helps ensure efficient cooling while minimizing unnecessary load on the engine ¹.

Basic Concepts of Fan Clutches

A fan clutch is a device that connects the engine-driven fan to the radiator. It operates by either mechanically or viscously coupling the fan to the engine. Mechanical fan clutches provide a fixed connection, whereas viscous fan clutches use a silicone-based fluid to vary the coupling between the fan and the engine. This variation allows the fan speed to be adjusted based on the engine’s cooling needs, leading to more efficient operation ².

Function and Operation of the 3928865 Fan Clutch

The Cummins 3928865 Fan Clutch functions by using a viscous coupling to regulate the fan speed. When the engine temperature is low, the fan clutch allows the fan to spin at a reduced speed, minimizing drag on the engine. As the engine temperature increases, the viscosity of the fluid within the clutch changes, allowing the fan to spin faster and increase airflow to the radiator. This dynamic adjustment helps maintain the engine within its optimal operating temperature range ³.

Key Features

The Cummins 3928865 Fan Clutch is characterized by its robust design and the use of high-quality materials. It incorporates advanced technology to enhance performance, including a durable housing and precision-engineered components. The clutch’s design ensures reliable operation under the demanding conditions typical of commercial truck applications.

Benefits of Using the 3928865 Fan Clutch

Utilizing the Cummins 3928865 Fan Clutch offers several advantages. It contributes to improved fuel efficiency by reducing the load on the engine when full fan speed is not required. Additionally, it helps minimize wear on engine components by maintaining optimal operating temperatures. The enhanced cooling performance provided by the fan clutch also contributes to the longevity and reliability of the engine.

Troubleshooting and Maintenance

Common issues with the 3928865 Fan Clutch may include slippage, which can be identified by a whining noise or inadequate cooling performance. Diagnostic procedures involve checking the clutch for proper operation and inspecting for signs of wear or damage. Regular maintenance, such as cleaning the clutch and ensuring it is free from contaminants, is recommended to ensure optimal performance and longevity.

About Cummins

Cummins Inc. is a global power leader that designs, manufactures, and distributes engines, filtration, and power generation products. With a history of innovation and a strong reputation in the commercial truck industry, Cummins is committed to delivering high-quality engine components. The company’s dedication to advancing technology and improving efficiency is evident in its product offerings, including the Cummins 3928865 Fan Clutch.

Fan Clutch Compatibility with Cummins Engines

The Cummins part number 3928865, a Fan Clutch, is designed to fit a variety of Cummins engines. This part is essential for maintaining optimal engine temperature by regulating the airflow through the radiator. Below is a detailed description of the engines with which this fan clutch is compatible:

B5.9 Series

• B5.9 G
• B5.9 GAS PLUS CM556

These engines, part of the B5.9 series, are equipped with the 3928865 fan clutch to ensure efficient cooling. The B5.9 G and B5.9 GAS PLUS CM556 models benefit from this component’s ability to maintain the radiator’s airflow, preventing overheating and ensuring peak performance.

ISB Series

• ISB CM2150
• ISB CM550
• ISB CM850
• ISB6.7 CM2250
• ISB6.7 CM2350 B101
• ISB6.7 G CM2180 B118

The ISB series engines, including the ISB CM2150, ISB CM550, ISB CM850, ISB6.7 CM2250, ISB6.7 CM2350 B101, and ISB6.7 G CM2180 B118, all utilize the 3928865 fan clutch. This clutch is critical for these engines as it helps manage the cooling system’s efficiency, ensuring that the engine operates within its optimal temperature range.

ISC Series

• ISC CM2150
• ISC CM850
• ISC8.3 CM2250

The ISC series engines, such as the ISC CM2150, ISC CM850, and ISC8.3 CM2250, are also compatible with the 3928865 fan clutch. This part ensures that these engines maintain the necessary cooling, which is vital for their longevity and performance.

ISL Series

• ISL CM2150
• ISL9 CM2150 SN
• ISL9 CM2250

The ISL series engines, including the ISL CM2150, ISL9 CM2150 SN, and ISL9 CM2250, are designed to work with the 3928865 fan clutch. This clutch helps these engines manage their cooling systems effectively, contributing to their overall efficiency and durability.

QSB Series

• QSB5.9 30 CM550
• QSB5.9 44 CM550
• QSB6.7 CM850 (CM2850)
• QSB7 CM2880 B117

The QSB series engines, such as the QSB5.9 30 CM550, QSB5.9 44 CM550, QSB6.7 CM850 (CM2850), and QSB7 CM2880 B117, are also compatible with the 3928865 fan clutch. This clutch is essential for these engines to maintain proper cooling, ensuring they run smoothly and efficiently.

Role of Part 3928865 Fan Clutch in Engine Systems

The part 3928865 Fan Clutch is an integral component in the efficient operation of engine systems, particularly in its interaction with the drive and fan components.

Interaction with the Drive Component

The fan clutch connects the engine’s drive mechanism to the cooling fan. This connection allows for variable engagement between the drive and the fan. As the engine operates, the fan clutch modulates the fan speed based on the engine’s temperature and load conditions. During low-temperature or low-load scenarios, the fan clutch disengages slightly, reducing drag on the engine and improving fuel efficiency. Conversely, under high-temperature or high-load conditions, the fan clutch engages more fully, ensuring adequate airflow through the radiator to maintain optimal engine temperature.

Interaction with the Fan Component

The fan clutch’s role extends to its direct influence on the fan’s operation. By adjusting the fan speed in response to engine demands, the fan clutch ensures that the fan operates at the most efficient speed for cooling. This dynamic adjustment prevents the fan from running at a constant high speed, which would otherwise increase fuel consumption and wear on the engine components. The fan clutch’s ability to vary fan speed also contributes to reduced noise levels during operation, enhancing the overall driving experience.

Conclusion

In summary, the part 3928865 Fan Clutch plays a significant role in maintaining engine efficiency and performance by intelligently managing the interaction between the drive and fan components. Its advanced design and compatibility with various Cummins engines make it a vital component for ensuring optimal engine cooling and longevity.