water circulation problem
 

so heres the situation, think the supra is having some water promblems...... the top radiator hose gets hot and the botom one stays cold, not actually let the engine run for long enough to over heat (still ok after about 25 mins of idling (not drove the car since i bought it yet)) but it doesnt sem it coling properly so i had a lok at the thermostat to see if it wasnt opening properly and its not there at all! so it wont be that, (or wil it) have taken the water pump out, although the gasket needs replacing the pump itself is fine, also tok the radiator out to check if it was blocked but thats fine, im thinking maybe a masive air lock or something? that posible? anybody had this problem and no what it is and or how to fix it?
thanks in advance alex

I suggest you buy a new OEM thermostat and housung seal. Install them.
Put in a new 50/50 mix of Toyota red antifreeze. Park you car nose high and "burp" the cooling system of air. Top off the coolant after voiding the system of air. Make sure your coolant expansion is filled to the correct level. Drive the car and bring it to operating temp. Monitor the coolant temp guage and stay close to home in case of issues.
You may find this will resolve your issue.

thanks for your reply, got a stat and seal today so will fit them, so to "burp" the system id park the nose high up and then just run it to get the air out? can i just ask why having the nose in the air would help? and would the fact that i actually have the rear of the car jacked up at the moment be causing those problems?
cheers alex

Positioning the car with the nose elevated, places the radiator at the high point of the cooling system. This promotes the air to migrate to the top tank of the radiator where it can then vent.
With the rear of the car raised, this may trap air in the block and not vent from the system.
When I burp the system, I raise the front of the car. Start it and run the engine at around 2000 RPM to get it up to temp, so the thermostat is open.
Allow to cool completly and top off the coolant (radiator & expansion tank).
Repeat the process untill when checked, the radiator is completly full (cold) and the expansion tank is at the proper level.