Caterpillar 3406 — Replace Thermostat
Repair & overhaul
For the Caterpillar 3406, from the Caterpillar operator's manual.
Applies to: Caterpillar 3406
Procedure
- Remove the hose clamps and the radiator hose from the thermostat housing.
- Remove the thermostat housing from the engine block.
- Remove the thermostat from the housing.
- Replace the seal located inside the housing and the gasket.
- Install a new thermostat in the thermostat housing and install the thermostat housing on the engine block.
- Install the radiator hose and tighten the hose clamps.
- Start the engine and inspect for leaks and proper operating temperature.
Specs & values
- Thermostat opening temperature: 180°F (82°C) bench test in atmospheric pressure.
- Thermostat should be fully open at approximately 197°F (92°C).
Full service-parts list: Caterpillar 3406 →
Source: Caterpillar operator's manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.