The DT466 engine coolant temperature sensor, often a single-wire stud-type sender, is typically located in the cylinder head next to the thermostat housing. This placement is consistent with similar systems used in tractors and combines. The sensor works by varying the resistance to ground, which in turn affects the reading on the temperature gauge. A common misconception is that the sensor receives battery power. Instead, power usually flows from the gauge to the sender, and the sender regulates the ground connection to control the gauge reading.
Troubleshooting a faulty temperature gauge can be complex. A sweeping gauge despite a seemingly disconnected sender wire suggests a potential issue with the gauge wiring. Using a voltmeter, rather than a test light, to check for power is crucial for accurate diagnosis. A wiring diagram specific to your DT466 and the engine serial number is essential for identifying the correct circuit. Clear pictures of the sender, its installation point, and the connector can further aid in troubleshooting.
An ether starting system, sometimes found in trucks, may incorporate a temperature switch to prevent ether use when the engine is warm. However, this doesn’t explain a sweeping gauge with a disconnected sender. Testing the old sender with an ohmmeter can help determine if it’s functioning correctly and if resistance changes with temperature variations. Comparing the readings to specifications in the service manual can confirm if the sender is within the acceptable range. Remember to consult the official wiring diagrams for your specific DT466 model to ensure accurate diagnosis and repair.
