I have a 94 buick skylark and my car is overheating and leaking water out of the reserve tank . I have replace?

I have replaced the thermostat, water pump and the radiator cap. Any ideas of why it would still be overheating and leaking?I have a 94 buick skylark and my car is overheating and leaking water out of the reserve tank . I have replace?I am sorry, but sounds as though you have a blown head-gasket. A 4 or 5 gas analyzer can confirm this in about 30 minutes. HC gas high in radiator proves it. luv ser. I can only assume your Radiator Fan is working.