Water out of the reservoir !!

Hello experts:

I have a strange problem , I have a Deawoo Lanos 1999 car with 1.6 (DOHC) engine ..

When I run the car more than 1/2 hour and turn off the engine .. the radiator's water reservoir start to spill the water out of the reservoir. It is boiling water !!

The car temperature indicator never goes over the half level of the temp indicator..

What happend with my car ??

The car is not hot ... and the water is boiling on the reservoir !!!

The water pump is new !!!

The motor run like a charm !!

Please somebody help me ,, !!!

 

Try a new radiator cap first. Hot water is lifting the springloaded bottom seal of the cap and that is how it is getting in the reservoir. (The top sealing gasket of the cap is what is keeping it from spilling directly out of the radiator onto the ground.)

If that does not do it, you have some serious engine issue, like gasket problem, where combustion gas is getting into your cooling system.

I happened to think of something else: Engines get hotter after they shut off. Some cars will allow the fan to come on, even after the car shuts off. I do not know if yours does or not. You might want to look into this to see if yours does.

Regardless, the fact it boils out of the reservoir, and not just INTO it, may also indicate that before you even took the trip, the water level was already too high in the reservoir. Make sure if you try another run, to see what happens, that the coolant level is no higher than where it is supposed to be. Often there are cold and hot engine marks on the reservoir to indicate where the level should be.