Thermostat stuck will it cause antifreeze to come out the overflow hose of the heater core?

The heater core has no overflow hose. Cooling system is a closed loop system and the only overflow hose is the one going from the radiator cap to the reservoir. A thermostat that is stuck closed will cause the engine to overheat. Drain and flush the radiator, replace the thermostat, install a 50/50 mix of antifreeze and distilled water, bleed air from the system. You may also need to replace the radiator cap. Be sure and replace these parts with OEM parts.

The heater core has no overflow hose. Cooling system is a closed loop system and the only overflow hose is the one going from the radiator cap to the reservoir. A thermostat that is stuck closed will cause the engine to overheat. Drain and flush the radiator, replace the thermostat, install a 50/50 mix of antifreeze and distilled water, bleed air from the system. You may also need to replace the radiator cap. Be sure and replace these parts with OEM parts.

The heater core has no overflow hose. Cooling system is a closed loop system and the only overflow hose is the one going from the radiator cap to the reservoir. A thermostat that is stuck closed will cause the engine to overheat. Drain and flush the radiator, replace the thermostat, install a 50/50 mix of antifreeze and distilled water, bleed air from the system. You may also need to replace the radiator cap. Be sure and replace these parts with OEM parts.