Q: all water comes out overflow tube on reserve tank

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I can put water in the radiator and reservoir and after it warms up it all comes out if the overflow tube on the resevoir. Also makes window fog up bad from the waterpump heater hose.
My car has an automatic transmission.

Hello, thank you for writing in. There are several issues with the cooling system that would trigger coolant entering the overflow tank. If the system is overheating, then the cooling system is doing its job by utilizing the overflow tank. If the system is not overheating you will want to look into the radiator cap and the thermostat. The pressure within the cooling system is critical to its performace, and the repair may be as easy as replacing the cap. It the problem persists after all of those inspections and potential corrections, you may have a blown head gasket. Only further testing will tell. For more help with diagnosis, contact our service department.

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