3957912
Valve Stem Seal
Cummins®

Introduction

The Valve Stem Seal 3957912 by Cummins is designed to enhance the operation of commercial truck engines. Its primary role is to maintain the integrity of the engine’s valve system by ensuring proper sealing and lubrication. This part contributes to overall engine performance and longevity.

Basic Concepts of Valve Stem Seals

A valve stem seal is a component in internal combustion engines that contains oil within the valve train while allowing the valve stem to move freely. It creates a barrier to prevent oil from leaking into the combustion chamber, which could lead to increased oil consumption and potential engine damage. The seal also maintains consistent lubrication around the valve stem, reducing wear and ensuring smooth operation ¹.

Role of the Valve Stem Seal 3957912 in Truck Operation

The Valve Stem Seal 3957912 provides a reliable seal around the valve stem, maintaining correct oil levels within the valve train. This is vital for the lubrication of moving parts. By preventing oil from entering the combustion chamber, the seal contributes to cleaner emissions and more efficient engine operation. It also helps reduce oil consumption, leading to cost savings and less frequent oil changes.

Key Features of the Valve Stem Seal 3957912

The Valve Stem Seal 3957912 is designed with several key features that enhance its performance and durability. It is constructed from high-quality materials resistant to wear and extreme temperatures. The seal’s design allows for a snug fit around the valve stem, ensuring effective containment of oil. Additionally, it incorporates advanced manufacturing techniques to ensure consistency and reliability in its function ².

Benefits of Using the Valve Stem Seal 3957912

Using the Valve Stem Seal 3957912 offers several benefits. It contributes to improved engine efficiency by maintaining optimal oil levels within the valve train. This results in reduced oil consumption, leading to cost savings over time. Furthermore, the seal enhances engine longevity by providing consistent lubrication and preventing oil from entering the combustion chamber, which can cause damage. The reliable performance of this seal also contributes to smoother engine operation and reduced maintenance requirements ³.

Troubleshooting and Maintenance

Common issues related to valve stem seals include oil leaks and increased oil consumption. These problems can often be traced back to worn or damaged seals. Regular inspection and maintenance of the valve stem seals can help identify potential issues before they lead to significant problems. It is recommended to follow the manufacturer’s guidelines for maintenance intervals and to replace seals as needed to ensure optimal performance and longevity of the engine.

About Cummins

Cummins Inc. is a global power leader that designs, manufactures, and distributes a wide range of power solutions, including engines, filtration, and emission solutions. With a history spanning over a century, Cummins has established a reputation for quality and innovation in the commercial truck industry. The company is committed to providing reliable and efficient engine components that meet the demanding requirements of commercial applications.

Valve Stem Seal 3957912 Compatibility with Cummins Engines

The Valve Stem Seal part number 3957912, manufactured by Cummins, is designed to fit a variety of Cummins engines. This seal is crucial for maintaining the integrity of the engine’s valve system by preventing oil from leaking past the valve stems. Below is a detailed breakdown of the compatibility of this valve stem seal with various Cummins engines.

Compatible Engines

• 4B3.9
• 6B5.9
• B4.5
• B5.9 CM2670 B166C
• B5.9 G
• B5.9 GAS PLUS CM556
• B6.7S
• G5.9
• G5.9 CM558
• ISB3.9 CM2220 B107
• ISB5.9 CM2880 B127
• ISB5.9G CM2180
• ISBE CM800
• QSB3.9 30 CM550
• QSB3.9 CM2880 B138
• QSB5.9 30 CM550
• QSB5.9 CM2880 B139
• QSB5.9G

Grouping of Compatible Engines

B Series Engines

• B4.5
• B5.9 CM2670 B166C
• B5.9 G
• B5.9 GAS PLUS CM556

G Series Engines

• G5.9
• G5.9 CM558

ISB Series Engines

• ISB3.9 CM2220 B107
• ISB5.9 CM2880 B127
• ISB5.9G CM2180

ISBE Series Engines

• ISBE CM800

QSB Series Engines

• QSB3.9 30 CM550
• QSB3.9 CM2880 B138
• QSB5.9 30 CM550
• QSB5.9 CM2880 B139
• QSB5.9G

Other Series

• 4B3.9
• 6B5.9

This valve stem seal is engineered to provide a reliable seal in the demanding environments of these engines, ensuring optimal performance and longevity.

Role of Part 3957912 Valve Stem Seal in Engine Systems

The Valve Stem Seal, identified by part number 3957912, is a component in maintaining the integrity and efficiency of various engine systems. Its primary function is to ensure a proper seal between the valve stem and the cylinder head, preventing oil leakage into the combustion chamber and maintaining optimal valve operation.

Integration with Engine Components

1. Cylinder Head and Cylinder Head Repair Kit: The Valve Stem Seal works in conjunction with the cylinder head to prevent oil from seeping past the valve stem. When performing repairs or replacements using a cylinder head repair kit, the Valve Stem Seal must be correctly installed to maintain the seal’s effectiveness.

2. Cylinder Head (Change) Assembly: During a cylinder head change assembly, the Valve Stem Seal plays a vital role in ensuring that the new cylinder head operates efficiently. Proper installation of the seal is necessary to avoid oil contamination in the combustion process.

3. Engine Repair Kit: Comprehensive engine repair kits often include Valve Stem Seals as a standard component. These seals are crucial for restoring the engine’s performance by ensuring that valves function without oil interference.

4. Exhaust Valve Kit and Intake Valve Kit: Both exhaust and intake valve kits require Valve Stem Seals to maintain the integrity of the valve system. The seals help in preventing oil from entering the combustion chamber, which can lead to performance issues.

5. Head and NEF Cylinder: When working with the engine head or NEF cylinder, the Valve Stem Seal ensures that the valve stems are well-sealed, contributing to the overall efficiency and longevity of the engine components.

6. Pistonless Overhaul and Overhaul Kit: In pistonless overhaul scenarios or when using an overhaul kit, the Valve Stem Seal is integral to the process. It ensures that the valve system remains oil-free, which is essential for the engine’s smooth operation.

7. Rebuild Kit and Retainer Valve Kit: During engine rebuilds, the Valve Stem Seal included in rebuild kits and retainer valve kits helps in achieving a tight seal around the valve stems, preventing oil leakage and ensuring reliable valve operation.

8. Seal Kit: A seal kit typically includes Valve Stem Seals as a key component. These seals are vital for maintaining the overall sealing integrity of the valve system.

9. Upper Engine Gasket Kit and Upper Engine Gasket Set: When installing an upper engine gasket kit or set, the Valve Stem Seal complements the gaskets by providing an additional layer of sealing around the valve stems, enhancing the engine’s performance and reliability.

Conclusion

The Valve Stem Seal 3957912 by Cummins is a critical component in maintaining the efficiency and longevity of commercial truck engines. By ensuring proper sealing and lubrication within the valve system, this part contributes to reduced oil consumption, cleaner emissions, and smoother engine operation. Regular maintenance and timely replacement of the seal are essential to sustain these benefits and ensure optimal engine performance.