4318947
Thermostat
Cummins®

Introduction

The Cummins 4318947 Thermostat is a critical component designed for commercial trucks, aimed at regulating engine temperature by controlling coolant flow through the engine cooling system. This regulation is essential for maintaining optimal engine performance and longevity ¹.

Basic Concepts of a Thermostat

A thermostat is a device that senses fluid temperature and controls its flow to maintain a stable temperature. In engine applications, the thermostat operates on the principles of thermal expansion and contraction. When the engine is cold, the thermostat remains closed, preventing coolant from flowing through the radiator. As the engine warms up, the thermostat opens, allowing coolant to circulate and cool the engine. This process ensures the engine operates within a specified temperature range, crucial for efficient performance and longevity ².

Role of the 4318947 Thermostat in Truck Operation

The Cummins 4318947 Thermostat regulates coolant flow based on engine temperature within the truck’s engine cooling system. When the engine is cold, the thermostat remains closed, allowing the engine to warm up quickly. Once the engine reaches the optimal operating temperature, the thermostat opens, permitting coolant to flow through the radiator, where it is cooled before returning to the engine. This cycle maintains the engine at an optimal temperature, ensuring efficient operation and protecting it from overheating damage.

Key Features

The Cummins 4318947 Thermostat is designed with several key features that enhance its performance and durability in heavy-duty applications. Its construction includes materials resistant to high temperatures and pressures found in commercial truck engines. The design allows for precise temperature control, ensuring the engine operates within the desired temperature range. Additionally, the thermostat is engineered to withstand the rigors of heavy-duty use, providing reliable performance over an extended period.

Benefits

Using the Cummins 4318947 Thermostat offers several benefits. It contributes to improved engine efficiency by ensuring the engine operates at the optimal temperature. This optimal operation can lead to extended engine life, as the thermostat helps prevent overheating, which can cause engine damage. Furthermore, the thermostat’s reliable performance under varying operating conditions ensures that the engine remains cool and efficient, regardless of the load or environmental conditions.

Troubleshooting and Maintenance

Common issues associated with thermostats include failure to open or close properly, which can lead to overheating or inefficient engine operation. Symptoms of a failing thermostat may include engine overheating, fluctuating temperature gauge readings, or a lack of heat from the cabin heater. Troubleshooting a thermostat involves checking for these symptoms and, if necessary, replacing the thermostat. Regular inspection and replacement of the thermostat as part of routine maintenance can help prevent these issues and ensure the engine operates efficiently.

About Cummins

Cummins Inc. is a global power leader that designs, manufactures, and distributes a wide range of power solutions, including diesel engines and related technologies. With a history spanning over a century, Cummins has established a reputation for quality, innovation, and customer satisfaction. The company’s commitment to these values is evident in its product line, including the Cummins 4318947 Thermostat, which is designed to meet the demanding requirements of commercial truck applications.

Compatibility of Thermostat 4318947 with Cummins Engines

The thermostat part number 4318947, manufactured by Cummins, is designed to fit a variety of Cummins engines. This part is crucial for maintaining optimal engine temperature by regulating the flow of coolant. Below is a detailed description of its compatibility across different engine models:

ISM Series Engines

• ISM CM570
• ISM CM570/870
• ISM CM876
• ISM11 CM876 SN

ISX Series Engines

• ISX CM570
• ISX CM870
• ISX CM871
• ISX12 CM2350 X102
• ISX12 G CM2180 EJ
• ISX12/ISX11.9 CM2250
• ISX15 CM2250
• ISX15 CM2250 SN
• ISX15 CM2350 X101

ISZ Series Engine

• ISZ13 CM2150 Z105

M11 Series Engines

• M11 CELECT
• M11 CELECT PLUS
• M11 MECHANICAL

N14 Series Engine

• N14 CELECT PLUS

QSM11 Series Engines

• QSM11 CM570
• QSM11 CM876

QSN14 Series Engine

• QSN14 CM876 N103

QSX Series Engines

• QSX11.9 CM2250 ECF
• QSX15 CM2250
• QSX15 CM2250 ECF
• QSX15 CM2350 X105

Role of Part 4318947 Thermostat in Engine Systems

In the orchestration of an engine’s thermal management, the 4318947 Thermostat is a pivotal component. It is strategically positioned within the thermostat housing, a robust enclosure designed to contain the thermostat and facilitate its interaction with the engine’s cooling system.

The thermostat operates on a simple yet effective principle: it regulates the flow of coolant between the engine and the radiator based on the engine’s temperature. When the engine is cold, the thermostat remains closed, blocking the coolant flow to the radiator. This allows the engine to warm up more quickly, enhancing efficiency and reducing emissions during the warm-up phase.

As the engine temperature rises, the thermostat gradually opens, allowing coolant to circulate through the engine and into the radiator, where it is cooled before returning to the engine. This continuous cycle ensures that the engine maintains an optimal operating temperature, which is essential for efficiency, performance, and longevity.

In the context of an overhaul kit, the 4318947 Thermostat is often included as a replacement part. Overhaul kits are comprehensive packages designed to refresh and restore engine components to like-new condition. The inclusion of a thermostat in these kits underscores its importance in maintaining the engine’s thermal equilibrium.

The thermostat’s interaction with other components is seamless and integral to the engine’s operation. It works in concert with the water pump, which circulates the coolant, and the radiator, which dissipates heat. The temperature sensor, often located near the thermostat, monitors the engine’s temperature and sends signals to the engine control unit (ECU), which may adjust the thermostat’s operation to optimize performance under varying conditions.

Conclusion

The Cummins 4318947 Thermostat is a key player in the engine’s cooling system, ensuring that the engine operates within its designed temperature range, thereby contributing to overall engine health and performance. Its precise temperature control, durability, and compatibility with a wide range of Cummins engines make it an essential component for maintaining optimal engine operation in commercial trucks.