remove the drain plug on the radiator.. and the fill cap on the reservior.. let the coolant drip out. then fill with water and run.. (leave the heater on at full blast even if its not cold.. and let the engine run.. turn off engine and let the coolant drop out.. do this a couple of times until the coolant is just plain water coming out.. that means that all the old coolant is coming out... not make sure you have at least 1/ 1/2 ballons of fluid out of the coolant system.. then tighten the drain plug on the radiator... now fill with 1/ 1/2 gallon of antifreeze and them the rest water... start up engine and keep adding water to the overflow container... let it idle or drive it for aboue 10-15 minutes and watch for the coolant level to drop i the coolant overflow tank and add some more water...
then next day check the coolant level in the coolant overflow tank and add some more water if its low, if not then you finished....
hope this helps... also to make sure i had no air pockets in the engine/hoses.. i grabbed most of the hoses and gave them a good squeeze to make sure that any air pockets moved along..... you can now turn the heater off if you dont need it... but make sure its on when trying to get the coolant in as its part of the coolant system....
