5I-7578 Water Temperature Sensor for Caterpillar E320B & E320C Excavators

Product Overview

The 5I-7578 water temperature sensor is a purpose-built coolant monitoring component for Caterpillar mid-size excavators. As a direct interchangeable replacement for OEM part 297-9314, it captures real-time coolant temperature data and delivers stable analog signals to the engine control system. This part is critical for keeping the S6K diesel engine within its optimal operating temperature range, preventing overheating damage and unplanned downtime on construction sites.

This sensor fits both routine preventive maintenance schedules and emergency repair scenarios. It is manufactured to match original equipment dimensions, thread specs and electrical parameters, enabling drop-in installation without modifying existing wiring harnesses or mounting ports.

Build & Performance Details

Precision Thermistor Core: Inside the brass probe sits a high-grade thermistor element that maintains consistent reading accuracy across the full working temperature range. It responds quickly to coolant temperature fluctuations, even under rapidly changing engine loads common in earthmoving work.

Solid Brass Housing: The entire sensor body is machined from corrosion-resistant brass. This material delivers excellent thermal conductivity for accurate readings, while the precision-cut mounting threads seat firmly in the engine coolant port to prevent leaks and loosening from machine vibration.

Dual-Stud Terminal Design: The two-bolt terminal configuration matches factory wiring connectors exactly. An insulating spacer between the two terminals prevents short circuits caused by dust, moisture or vibration, maintaining steady signal transmission during long hours of heavy operation.

Wide Environmental Tolerance: The sensor operates reliably from -40°C up to 120°C, covering both cold-weather startup conditions and high-temperature heavy-load working environments typical of construction and mining job sites.

Technical Specifications

Compatible Machinery List

This temperature sensor is engineered for direct fit on the following Caterpillar construction equipment:

• Caterpillar E320B Hydraulic Excavator

• Caterpillar E320C Hydraulic Excavator

• Caterpillar E323D Hydraulic Excavator

• Caterpillar E311C Compact Excavator

• Caterpillar E315C Excavator

• Caterpillar E312B Excavator

It also works as a compatible replacement for additional equipment models built with the S6K engine platform. We recommend confirming your original part number before placing an order to ensure proper fitment.

Installation & Maintenance Tips

For proper installation, clean the coolant port threads thoroughly before fitting the sensor. Apply a small amount of coolant-safe thread sealant to the threaded section, then tighten to the manufacturer's recommended torque specification. Always verify that the sensor probe is fully submerged in coolant after installation to avoid inaccurate readings.

When replacing a failed sensor, take the opportunity to inspect the wiring harness and connector pins for corrosion or wear. Erratic temperature gauge readings, frequent overheating alarms or cold-start performance issues are common signs that a water temperature sensor needs replacement.

Ordering & Supply Information

We offer this 5I-7578 sensor as part of our complete line of Caterpillar excavator replacement components. All parts are manufactured and inspected to match OEM equivalent quality standards. We process orders based on customer requirements, with flexible order quantities to support both single repair jobs and bulk fleet maintenance programs.

If you need help cross-referencing part numbers or confirming compatibility with your specific equipment model, feel free to reach out to our team for detailed support.