cooling system problems

I have just bought an 89 dodge dynasty w\175k for a meer $30. I first had to change the waterpump and the serpentine-belt to get running again. It ran great for a while until it started overheating. Major leaking had accured from the top radiator hose. I've changed the hose, thermostat, and the clamps; now I cant seem to keep the pressure in the cooling system. The Mix(water & antifreez), keeps coming from the end of the top radiator hose closest to the rad dispite tightening and loosening the clamp. I can't pinpoint the reason for over heating, or the pressure buildup in the system when I start the car. Any help would be a blessing.

Have the system pressure tested to see where the leak is. Usually, you can hear a hiss somewhere and that'll tell you where the problem is.

May have blown head gasket. That will cause excessive pressure in the cooling system. With engine cool, fill radiator to top, leave cap off, start the engine and look for bubbles in the coolant.

What engine? 4 cyl or 6 cyl.?