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Do you mean thermoswitch?

posted by  someone claiming to be JohnB on  Thu Feb 19 01:50 CST 2004 [RELATED]

the thermostat is mechanical and in the engine block, immersed in coolant.

the thermoswitch is in the radiator, immersed in coolant.

The thermostat controls coolant flow from the engine to the radiator...engine/coolant gets hot, thermostat opens to allow hot coolant to flow from the engine and cooled coolant to flow from the radiator to the engine.

The thermoswitch activates the radiator fans to move more air through the radiator when the top of the radiator gets warm enough to cycle the switch.

Not unusual for the thermoswitch to fail closed...in fact, you WANT it to fail closed vice open because if it fails closed, the worst that happens is you overcool the radiator or kill a battery. If it fails open, you risk overheating an engine in slow traffic and potential engine seizure.





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New 945 cooling fan problem
posted by  945  on Wed Feb 18 20:27 CST 2004 >


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