more liquid aint gonna cool it any better if your water pump aint workn or ur t stat isnt opening and dont waste ur time with a used rad u cant tell if its had stop leak or what not jus get a new one if thats yr problem but check your waternpump and t stat a good was to check ur t stat is place it in a pan of water then boil the water youll be able to see it open once the water boils...you def dont wanna keep over heatn that motor or ur gonna have major problems warped head hg and over time berings
