1991 Celica 1.6L 4AFE OVerheating Issue

[denalipro]

Hi folks,
This is for a 1.6L Celica that has 250,000miles on it. Ignore the rusty appearance
of the radiator fluid. For testing purposes, I have filled the radiator with
tap water.
I am having an overheating issue with the car and a loss of coolant.
Pretty much what happens is when you start the car, the temperature starts
rising steadily and reaches the critical red mark. Simulataneously, you hear
bubbling/hissing from the hood and when you open the hood you see fluid bubbling
from the overflow tank area as it can be seen from the video.
What the video shows is when the car is idling. When you are driving, this all
is happening but really fast...

HERE IS THE VIDEO of what is happening:
The video shows bubbling a few seconds after the engine has been turned off. With the engine on,
the bubbling was more intense.
http://s703.photobucket.com/albums/w...ating%20Issue/

What seems to be happening:
============================
Somehow the radiator is shooting the water into the
overflow tank quite a bit so not much seems to be going back and forth
between the radiator and the engine and as a result, the car is overheating.

Turning on the heater helps a little reduction of temperature.

WHAT IS NOT CAUSING THE OVERHEATING:
====================================
1) I know it is not the waterpump because today I replaced the waterpump and symptoms
are the same.
2) It is not the thermostat because I replaced with a new one and symptoms are the same.
For now, I have taken the thermostat out to keep things simple.
3) I checked the upper and lower radiator hoses in the front of the engine and took them
off and cleaned them and there are no leaks up front. They are getting super hot so I
know water is circulating.
4) There are a few hoses on the back fo the engine also, under the fuel injectors but I
have not inspected them. THere do not appear to be any leaks coming from them.

So if you have any suggestions, please let me know. thanks...

[PEN]

Here's one problem I see, your coolant looks like cow shit. From the seriously nasty looking coolant I'd say you have blockage somewhere not allowing decent flow making the engine run too hot.

[PEN]

Oh that can also be symptoms of a blown head gasket or just before.

[RobMilkshakes]

Well if its only bubbling once it reaches a very high temperature then the radiator cap is doing its job. I would look into replacing the cap though, seems simple but if the cap is not allowing the system to pressurize then the coolant can boil at a lower temperature.

Also, there is the potential that the cooling system is partially air locked.

[yadpwns]

Sounds like a blown head gasket to me. Try some type of headgasket sealant a good one would be seal x , it goes in your radiator along with some coolant and then try to diagnosed again. That could possibly solve your problem for a little while and if it does then your looking at a headgasket replacement.

[denalipro]

Thank you folks for your kind responses...