wont start need jump?

i have a 88 tbird 5.0 replaced battery post, battery, celinoid, starter, headgasket(blew cause of overheating problem) car is still doing same thing. will start up great in morning but will sometime start getting hot,add water. then will when i stop wont start i need jump(brand new battery)will start most of time with jump but might have to let sit until next morning. will try to turn over can hear fuel, when car is running hear bubbling inside car notice leak under i think heater on starter side. im about to junk it. please help.