I have a 03 Nissan 350z
and So I am in the process of bleeding my system it was overheating but it seems like the old owner did not bleed it properly as there was no bleeder valve but I got one installed it and I have been trying to bleed it but I filled the radiator with water and the valve with water and it seems like the valve is taking infinite water idk if it’s bc I’m using a hose or what but I looked under the car when on and I didn’t notice any leaks... after about 8-9 mins of the car being on the heat also goes cold and also last point everytime I start the car the overflow tank gets even more to the point where it got full yesterday and I had to empty it a little bit
and whenever I get done with the starting part and waiting for the fans after I go to check it I hear little to no hissing but the valve looks almost empty and all the hoses are getting hot except for the driver side heat core hose is warmish and seems to get hotter after I turn the car off and put more water in

 

Also whenever I open the radiator cap and try to add water into there the valve is almost instantly full

 

How's your head gasket?

 

well I don’t know how it is but I ended up stopping the bleeding process and I really didn’t hear air come out the whole time except the last time I unscrewed the cap than I heard a lot of air come out and I’ve ran the car for 40 mins driving and it didn’t overheat at all it stayed at temp and I drove it to work 30 mins and back and it didn’t overheat then so I am gonna assume the issue is good and my heat is staying hot hot now so I don’t really see any issues

 

Well another way to fill it up 100% is a slow slow process. Basically you just pour your water/coolant in through the filler neck and keep filling it as the water pump sucks it up. When the water stops sinking in, it's full