My coolant keeps backing up into my overflow tank. I will open the radiator cap and there will be no fluid in the top hoses or in the radiator cap T fitting. I will refill the cooling system by opening the radiator cap, unbolting the overflow and lifting it up until there is fluid in the radiator cap T. I will then start the car and burp the air out again lifting the overflow to transfer fluid. Is this normal for the top hoses to be empty when the engine is cold?

I noticed the coolant problem in winter when I would only get heat when the engine was under acceleration. If i was riding behind someone down a hill, the blower would blow cold air until i started going up another hill or was accelerating.

I have replaced the radiator cap and it is still filling up the overflow. I also did a compression test to check the head gasket.


Any help would be very much appreciated.

 

I've helped several family members change their water pumps lately (different makes/models). Since you mention the heat/acceleration symptom... I'd go with air trapped in the system. Some cars are more of a pain than others (to bleed). How many times have you bled the system? What did you do exactly?

 

I have only been letting it run with the cap off to let air escape.

 

Sounds like you still have air in the system. I had the same problem with my brother in laws truck. Had to bleed the system 3 times. How many times have you bled the system? Did you turn the heater on (helps)? How long did you let it run?

 

Or it is a cracked head (sry).


If bleeding it again does not fix it - have a garage use an exhaust sniffer to detect exhaust gas at the radiator fill neck (cap off/engine running).