Overheating problem, help much appreciated

We've changed the radiator, changed the heater core, changed the radiator hoses, put in a new radiator hose stem, and a new radiator cap. The problem is that is heats up veru quickly while driving any distance. The coolant seems to be leaking out from under the cap, or the cap seems to be loosening whenever it heats up and cools down. It leaks all the radiator fluid out. So here's my question, do I need a new tank, a new cap, or what? No clue what the tank is officially called. And if I do need a new tank, what would it be called and where could I get it? Like I said, help is very much appreciated. Thanks,
frickenlucy

It sounds like your radiator cap is on the fritz. Air in the cooling system could cause the overheating, also.

Welcome to AF frickenlucy.

The tank is called the resivoir.

Did you purge any air from the cooling system after you replaced all that stuff ??

THough not knowing what year or engine you have, you could possibley have a head or intake gasket bad causing the quick heat ups.

The year of the car is 1995, and by purging the air from the cooling system do you mean turning on the heater or cooler in the car? If so, yes, I've turned on the heater while driving, and it seems to help somewhat.

Its best to purge the air from the system when its parked.

Open the radiator cap or resivoir cap and let it run making sure the coolant level is correct.

With it spewing out the resivoir cap that might need replaced, but it does sound like you are having other problems causing the overheating.
Might try and do a compresion test to see if the head gaskets are bad.

Good Luck