4987978
Cylinder Head
Cummins®

The Cummins 4987978 Alternator is a component designed for use in commercial trucks. Its purpose is to generate electrical power to charge the vehicle’s battery and to supply power to the truck’s electrical systems while the engine is running. This part is significant in ensuring that the truck’s electrical components operate efficiently and reliably, contributing to the overall performance and uptime of the vehicle ¹.

Basic Concepts of Alternators

An alternator is a device that converts mechanical energy into electrical energy. It functions within a vehicle’s electrical system by using a rotor that spins within a stator to generate an alternating current (AC), which is then converted into direct current (DC) by a rectifier. This DC power is used to charge the battery and to power the truck’s electrical components. The alternator also plays a role in regulating electrical power to maintain a consistent voltage level, ensuring that the electrical systems operate within their designed parameters ².

Purpose of the 4987978 Alternator in Truck Operation

This Cummins part is specifically designed to integrate into the electrical system of a commercial truck. Its primary function is to charge the truck’s battery while the engine is running, ensuring that the battery maintains a sufficient charge to start the engine and to power the truck’s electrical systems when the engine is off. Additionally, the alternator supplies power to the truck’s electrical components, such as lights, radios, and other accessories, while the engine is operating ³.

Key Features of the 4987978 Alternator

The 4987978 Alternator is constructed with high-quality materials and features a robust design that enhances its performance and durability. Its build quality includes precision-machined components and heat-treated parts that are designed to withstand the rigors of commercial truck operation. The alternator also incorporates advanced technology to improve efficiency and reliability, ensuring that it can meet the demands of heavy-duty applications ⁴.

Benefits of Using the 4987978 Alternator

This part offers several advantages for commercial truck operators. Its improved efficiency means that it can generate more power with less strain on the engine, contributing to better fuel economy. The alternator’s reliability is enhanced by its durable construction and advanced technology, reducing the likelihood of failures and downtime. Additionally, its compatibility with Cummins engines ensures that it can deliver optimal performance when integrated into the truck’s electrical system ¹.

Troubleshooting and Maintenance Suggestions

To ensure the optimal performance and longevity of the 4987978 Alternator, it is important to perform routine maintenance checks and to address any issues promptly. Common issues with alternators can include worn brushes, faulty diodes, or a loose belt. Regular inspections of the alternator’s connections, belt tension, and overall condition can help identify potential problems before they lead to failure. Additionally, keeping the alternator clean and free of debris can prevent overheating and extend its service life ².

Cummins Corporation

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 reputation for quality, Cummins is committed to providing high-performance components for a variety of applications, including commercial trucks. The company’s dedication to manufacturing excellence is evident in its products, such as the 4987978 Alternator, which are designed to meet the demanding requirements of heavy-duty operations ¹.

Cummins Alternator 4987978 Compatibility with Engine Models

The Cummins Alternator part number 4987978 is designed to be compatible with several engine models, ensuring reliable power generation across various applications. This alternator is engineered to work seamlessly with the following Cummins engine series:

ISL9 CM2150 SN and QSC8.3 CM850 (CM2850)

The ISL9 CM2150 SN and QSC8.3 CM850 (CM2850) engines are part of Cummins’ lineup of high-performance engines. The 4987978 alternator is specifically tailored to meet the power demands of these engines, providing efficient and consistent electrical output. This compatibility ensures that both engine models can maintain optimal performance, whether in heavy-duty trucks, industrial applications, or other demanding environments ¹.

QSL8.9 CM2150 L141 and QSL9 CM850 (CM2850)

The QSL8.9 CM2150 L141 and QSL9 CM850 (CM2850) engines also benefit from the 4987978 alternator. These engines are known for their durability and efficiency, and the alternator is designed to support these characteristics by delivering reliable electrical power. The compatibility of this alternator with these engine models ensures that users can expect consistent performance and longevity, making it a suitable choice for various applications, including construction equipment, marine vessels, and power generation systems ¹.

Role of Part 4987978 Alternator in Engine Systems

The part 4987978 alternator is integral to maintaining the electrical systems within the engine. It works in conjunction with several key components to ensure optimal engine performance and reliability.

Interaction with the Cylinder Head

The alternator, including part 4987978, is often driven by a belt connected to the crankshaft, which is directly influenced by the cylinder head’s operations. The cylinder head houses the valves and integrates with the combustion chamber, playing a significant role in the engine’s power cycle. As the engine runs, the alternator generates electricity to power the vehicle’s electrical systems and recharge the battery, ensuring that the cylinder head and other components receive consistent power ².

Support for Fuel Injectors

Fuel injectors are precision components that deliver fuel into the combustion chamber. The alternator ensures that the injectors receive a stable electrical supply, which is essential for their accurate operation. Consistent power from the alternator allows the injectors to maintain precise fuel delivery, contributing to efficient combustion and overall engine performance ³.

Enhancing Performance Parts

Performance parts, such as upgraded ECUs, cold air intakes, and exhaust systems, rely on a robust electrical supply to function at their best. The alternator, including part 4987978, provides the necessary power to these components, ensuring they operate within their designed parameters. This reliable power supply helps in maximizing the performance enhancements these parts offer, leading to improved engine output and efficiency ⁴.

Conclusion

The Cummins 4987978 Alternator plays a crucial role in the electrical system of commercial trucks, ensuring efficient and reliable power generation. Its compatibility with various Cummins engine models, robust construction, and advanced technology make it a dependable component for heavy-duty applications. Regular maintenance and prompt troubleshooting are essential to maximize the alternator’s performance and longevity, contributing to the overall efficiency and reliability of the vehicle’s electrical system.