No heat, losing coolant through reservoir tank?

MATT SNEYD

MEMBER
2014 KIA SORENTO
3.3L
6 CYL
4WD
AUTOMATIC
128,600 MILES

No heat/blowing cold air. Replaced thermostat, replaced overflow tank, replaced radiator cap, had coolant flush done. Car blows hot heat while burping system. Test drive took 3/10th of a mile and lost heat. Coolant being forced out overflow reservoir vent hole. Crimped reservoir tank line and it came off at radiator neck. System building too much pressure. Oil not milky, no leaks showing on ground. Cannot troubleshoot any further.

1 Reply

JACOBANDNICKOLAS

MECHANIC
109,747 POSTS

Hi,

You may have a failed head gasket. If it is allowing compressed air from the engine to enter the cooling system, this can happen.

Do me a favor. When the engine is cold, remove the radiator cap and start the engine. See if coolant blows out. If it does, the head gasket is my first suspect. Also, check to see if there are air bubbles in the coolant while it is running.

Take a look through this link and let me know your thoughts. It discusses different things to check, one of which you already mentioned isn't happening (mixing of oil and coolant).

https://www.2carpros.com/articles/head-gasket-blown-test

Let me know your thoughts. If you suspect it could be a head gasket, I recommend checking engine compression to see if there is a cylinder or two with lower compression.

Here is a link that explains how that is done:

https://www.2carpros.com/articles/how-to-test-engine-compression

Let me know what you find or if you have other questions.

Take care and Happy Thanksgiving.

Joe