3930838
Belt Tensioner Bracket
Cummins®

The Belt Tensioner Bracket (Part #3930838) by Cummins is a component designed to ensure the proper functioning of belts within a truck’s engine system. This part plays a significant role in maintaining the efficiency and reliability of commercial trucks by ensuring that belts remain under the correct tension, which is vital for the operation of various engine components.

Basic Concepts of Belt Tensioner Brackets

A Belt Tensioner Bracket is a part of the engine system that supports the tensioner, which in turn maintains the appropriate tension on the belts driving accessories such as the alternator, water pump, and air conditioning compressor. It operates by allowing the tensioner to move as needed to keep the belt at the correct tension, compensating for wear and thermal expansion ¹.

Purpose of the 3930838 Belt Tensioner Bracket

The 3930838 Belt Tensioner Bracket is integral to the operation of a truck’s engine system. It supports the tensioner mechanism, which ensures that belts remain taut. This is important for the efficient transfer of power to engine accessories and for preventing belt slippage, which can lead to decreased performance and potential damage to the engine components ².

Key Features

The 3930838 Belt Tensioner Bracket is characterized by its robust design and the use of high-quality materials. It is engineered to withstand the rigors of heavy-duty applications. The bracket’s design includes features that enhance its performance and durability, such as precise mounting points and a structure that accommodates the movement of the tensioner ³.

Benefits

Using the 3930838 Belt Tensioner Bracket can lead to improved engine efficiency, as it helps maintain the correct belt tension, which is necessary for the optimal operation of engine accessories. It also contributes to reduced wear on belts and enhances the reliability of the truck’s engine system by ensuring that belts operate within their designed parameters ⁴.

Installation and Compatibility

Proper installation of the 3930838 Belt Tensioner Bracket is important for its function and the overall performance of the engine system. Installation procedures may vary depending on the truck model, and it is important to follow manufacturer guidelines to ensure correct fitting and operation. The bracket is compatible with various Cummins engines and is designed to meet the demands of different commercial truck makes and models ⁵.

Troubleshooting and Maintenance

Common issues with the 3930838 Belt Tensioner Bracket may include wear or damage to the bracket itself or the tensioner it supports. Regular inspection and maintenance can help identify potential problems early. Troubleshooting steps may involve checking for proper tensioner movement, signs of wear on the bracket, and ensuring that all mounting points are secure ⁶.

Performance and Reliability

The 3930838 Belt Tensioner Bracket is designed to perform reliably under various operating conditions, including heavy-duty applications and extreme environments. Its performance characteristics are a result of its design and the quality of materials used, which contribute to its durability and effectiveness in maintaining belt tension ⁷.

Cummins: A Brief Overview

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 commitment to quality, Cummins has established a reputation for producing reliable and efficient engine components. The company’s product offerings cater to a wide range of industries, including commercial trucking, where reliability and performance are paramount.

Belt Tensioner Bracket 3930838 Compatibility with Cummins Engines

The Belt Tensioner Bracket part number 3930838, manufactured by Cummins, is designed to fit a variety of Cummins engines. This part plays a role in maintaining the proper tension of the engine’s serpentine belt, ensuring optimal performance and longevity of the belt and related components.

Compatibility with Specific Engine Models

• 4B3.9
• 6B5.9
• B5.9 G
• B5.9 GAS PLUS CM556
• ISB CM550
• ISB3.9 CM2220 B107
• ISB5.9 CM2880 B127
• ISB5.9G CM2180
• QSB5.9 30 CM550
• QSB6.7 CM850 (CM2850)
• QSB7 CM2880 B117

Grouping of Compatible Engines

The Belt Tensioner Bracket 3930838 is compatible with several Cummins engines, grouped by their model and specifications:

• ISB Series Engines:

  • ISB CM550
  • ISB3.9 CM2220 B107
  • ISB5.9 CM2880 B127
  • ISB5.9G CM2180

• QSB Series Engines:

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

• Other Models:

  • 4B3.9
  • 6B5.9
  • B5.9 G
  • B5.9 GAS PLUS CM556

This compatibility ensures that the Belt Tensioner Bracket can be effectively used across a range of Cummins engines, providing a reliable solution for maintaining belt tension and preventing potential mechanical issues.

Role of Part 3930838 Belt Tensioner Bracket in Engine Systems

The Belt Tensioner Bracket (Part 3930838) is an integral component in maintaining the proper tension of the drive belt within an engine system. This part securely mounts the tensioner, which is responsible for applying the correct amount of tension to the belt as it wraps around various pulleys.

When the engine is operational, the drive belt transfers power from the crankshaft to auxiliary components such as the alternator, water pump, and other pulley-driven accessories. The Belt Tensioner Bracket ensures that the belt remains taut, preventing slippage that could lead to inefficient operation or complete failure of these components.

In the context of the alternator drive, the Belt Tensioner Bracket works in conjunction with the alternator pulley to maintain consistent belt tension. This ensures that the alternator receives the necessary power to generate electricity for the vehicle’s electrical system.

Similarly, for the water pump drive, the bracket helps maintain the belt’s tension as it drives the water pump, which is essential for circulating coolant through the engine to prevent overheating.

The connection between the Belt Tensioner Bracket and the tensioner itself is designed to allow for minor adjustments in belt tension as the belt wears or stretches over time. This adaptability ensures that the belt continues to perform efficiently throughout the vehicle’s lifespan.

Conclusion

In summary, the Belt Tensioner Bracket (Part 3930838) plays a significant role in the reliable operation of the engine’s accessory drive system by ensuring that the drive belt maintains the appropriate tension across all pulleys, including those for the alternator and water pump.