3935991 Image1

3935991
Fuel Injection Pump
Cummins®

DISCONTINUED

Cummins®
Genuine OEM Part

This truck part is made by Cummins®. We guarantee that all of our parts are from the OEM (original equipment manufacturer), ensuring a proper fit and quality manufacturing.

Manufacturer Warranty*
DESCRIPTION

Introduction

The Cummins 3935991 Fuel Injection Pump is a critical component in the operation of commercial trucks, ensuring precise fuel delivery to the engine cylinders. This precision is essential for maintaining optimal engine performance, fuel efficiency, and emissions control 1.

Basic Concepts of Fuel Injection Pumps

Fuel injection pumps deliver fuel to engine cylinders at the correct timing and pressure. In diesel engines, this component significantly influences combustion efficiency and engine performance. Pumps can be mechanical, relying on engine-driven components, or electronic, using sensors and electronic controls for precise fuel delivery 2.

Role of the 3935991 Fuel Injection Pump in Truck Operation

This Cummins part is designed to enhance truck operation by ensuring exact fuel delivery timing and pressure. This precision is vital for maintaining optimal engine performance, fuel efficiency, and emissions control. The pump works with other engine components to ensure efficient combustion of the fuel-air mixture 3.

Key Features of the 3935991 Fuel Injection Pump

The 3935991 boasts several key features contributing to its effectiveness. Its design incorporates high-quality materials for durability and reliability. It may include technological advancements such as improved seals and precision-machined components to enhance performance and longevity 4.

Benefits of Using the 3935991 Fuel Injection Pump

Utilizing this part offers several benefits, including improved fuel efficiency, enhanced engine performance, and increased reliability. The precise fuel delivery optimizes combustion, leading to better overall engine operation and reduced maintenance requirements 5.

Common Issues and Troubleshooting

Common issues with the 3935991 may include leaks, inconsistent fuel delivery, or pump failure. Troubleshooting involves inspecting the pump for wear, checking fuel lines for blockages, and ensuring secure connections. Replacing worn components or the entire pump may be necessary to restore optimal performance 6.

Maintenance Tips

To ensure longevity and optimal performance of the 3935991, regular maintenance is essential. This includes inspecting the pump for wear, cleaning fuel lines and filters to prevent blockages, and replacing worn components as needed. Adhering to a routine maintenance schedule can help prevent unexpected failures and extend the pump’s lifespan 7.

Integration with Engine Management Systems

The 3935991 is designed to integrate seamlessly with modern engine management systems. This integration allows for optimized fuel delivery and enhanced engine performance. The pump communicates with the engine control unit (ECU) to adjust fuel delivery based on real-time data, ensuring efficient engine operation under various conditions 8.

Environmental Impact and Efficiency

This Cummins part plays a role in reducing emissions and improving engine efficiency. By delivering fuel with precision, the pump ensures complete combustion, which reduces harmful pollutant emissions. Additionally, efficient fuel delivery contributes to better fuel economy, minimizing the environmental impact of truck operations 9.

Historical Development and Technological Advancements

The development of fuel injection pumps has evolved significantly, leading to models like the 3935991. Technological advancements in materials, manufacturing processes, and electronic controls have improved the performance and reliability of modern fuel injection pumps. The 3935991 represents these advancements, offering enhanced functionality and durability 10.

Cummins Corporation

Cummins Corporation is a renowned manufacturer of diesel engines and components, known for quality and innovation. The company has a history of developing reliable and efficient engine components, and the 3935991 is a testament to their commitment to excellence in diesel engine technology 11.

Compatibility

The 3935991 is designed to integrate seamlessly with various engine models, ensuring optimal performance and reliability. This part is engineered to meet the stringent demands of various engine applications, providing precise fuel delivery and efficient combustion.

Engine Compatibility

  • 4B3.9: The 3935991 is specifically tailored to work with the 4B3.9 engine. This engine is known for its robust performance and is widely used in various industrial and commercial applications. The compatibility ensures that the pump can handle the specific fuel requirements and operational conditions of the 4B3.9 engine.

  • Grouped Applications: Beyond the 4B3.9, the 3935991 is also suitable for other engines within the same family or similar specifications. This grouping allows for a broader application range, ensuring that the pump can be utilized in multiple engine models that share common design and operational parameters.

The design of the 3935991 includes advanced features such as high-pressure fuel delivery, precise timing control, and durability to withstand demanding engine operation conditions. This ensures that the pump not only fits well with the engines but also enhances their overall performance and efficiency 12.

Role in Engine Systems

The 3935991 is integral to the efficient operation of modern engine systems. It works in conjunction with several key components to ensure optimal fuel delivery and engine performance.

Integration with Base Fuel Pump

The base fuel pump draws fuel from the tank and delivers it to the fuel injection pump. The 3935991 receives pressurized fuel from the base fuel pump and further increases the pressure to the levels required for injection into the combustion chambers. This high-pressure fuel is essential for achieving the fine atomization needed for efficient combustion 13.

Interaction with Fuel System Components

Once the fuel is pressurized by the 3935991, it is distributed to the fuel injectors. The fuel injection pump ensures that each injector receives a precise amount of fuel at the exact moment needed during the engine cycle. This timing and precision are vital for maintaining engine efficiency, reducing emissions, and enhancing overall performance 14.

Coordination with Engine Control Unit (ECU)

The engine control unit (ECU) plays a significant role in regulating the operation of the 3935991. The ECU monitors various engine parameters such as load, speed, and temperature. Based on this data, it sends signals to the fuel injection pump to adjust the fuel delivery accordingly. This dynamic interaction ensures that the engine operates within optimal parameters under varying conditions 15.

Contribution to Overall Fuel Efficiency

By precisely controlling the fuel delivery, the 3935991 contributes significantly to the overall fuel efficiency of the engine. The high-pressure injection allows for better fuel atomization, leading to more complete combustion and reduced fuel consumption. This efficiency is further enhanced by the ECU’s real-time adjustments, ensuring that the engine always operates at peak performance 16.

Conclusion

The Cummins 3935991 Fuel Injection Pump is a key component in the fuel delivery system, working seamlessly with the base fuel pump, fuel injectors, and ECU to ensure efficient and precise fuel delivery. This ultimately contributes to the engine’s performance and fuel economy, making it an essential part of modern diesel engine technology.

  1. Mollenhauer, K., & Tschoeke, H. (2010). Handbook of Diesel Engines. Springer.

    ↩

  2. Lakshminarayanan, P. A., & Nayak, N. S. (2011). Critical Component Wear in Heavy Duty Engines. John Wiley & Sons.

    ↩

  3. Dixon, J. (2014). Modern Diesel Technology: Heating, Ventilation, Air Conditioning, Refrigeration, 2nd Edition. Cengage Learning.

    ↩

  4. Majewski, A., & Jaskelainen, H. (2023). Diesel Emissions and Their Control: Second Edition. SAE International.

    ↩

  5. Mollenhauer, K., & Tschoeke, H. (2010). Handbook of Diesel Engines. Springer.

    ↩

  6. Lakshminarayanan, P. A., & Nayak, N. S. (2011). Critical Component Wear in Heavy Duty Engines. John Wiley & Sons.

    ↩

  7. Dixon, J. (2014). Modern Diesel Technology: Heating, Ventilation, Air Conditioning, Refrigeration, 2nd Edition. Cengage Learning.

    ↩

  8. Majewski, A., & Jaskelainen, H. (2023). Diesel Emissions and Their Control: Second Edition. SAE International.

    ↩

  9. Mollenhauer, K., & Tschoeke, H. (2010). Handbook of Diesel Engines. Springer.

    ↩

  10. Lakshminarayanan, P. A., & Nayak, N. S. (2011). Critical Component Wear in Heavy Duty Engines. John Wiley & Sons.

    ↩

  11. Dixon, J. (2014). Modern Diesel Technology: Heating, Ventilation, Air Conditioning, Refrigeration, 2nd Edition. Cengage Learning.

    ↩

  12. Majewski, A., & Jaskelainen, H. (2023). Diesel Emissions and Their Control: Second Edition. SAE International.

    ↩

  13. Mollenhauer, K., & Tschoeke, H. (2010). Handbook of Diesel Engines. Springer.

    ↩

  14. Lakshminarayanan, P. A., & Nayak, N. S. (2011). Critical Component Wear in Heavy Duty Engines. John Wiley & Sons.

    ↩

  15. Dixon, J. (2014). Modern Diesel Technology: Heating, Ventilation, Air Conditioning, Refrigeration, 2nd Edition. Cengage Learning.

    ↩

  16. Majewski, A., & Jaskelainen, H. (2023). Diesel Emissions and Their Control: Second Edition. SAE International.

    ↩

SPECIFICATIONS

Package Dimensions
14.1 x 14.0 x 10.88 in
Weight
16.98 lb
* This information is provided as is and may be out of date. Please contact us or the manufacturer to verify warranty coverage.
* Variable geometry turbocharger and electronic actuator repairs are not eligible to be claimed as over-the-counter under New or ReCon parts warranty for parts installed after October 1, 2018.
* Diesel Oxidation Catalyst (DOC), Diesel Particulate Filter (DPF), Selective Catalyst Reduction (SCR) catalyst, and Electronic Control Module (ECM) repairs are not eligible to be claimed as over-the-counter under New or ReCon parts warranty for parts installed after January 1, 2020.
* These restrictions are only applicable to New parts and ReCon parts coverages for the components listed above sold to a customer in the US or Canada. All other coverages are excluded. All other regions are excluded.

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