Ive Epica 2005 its constantly creating Gas from the Engin to the Radiator and get heatup ive change radiator , AC compresor , Gear , Engin Head nothing help out. What to do?

i've never seen an epica in my area... do u see any bleeder screws in the radiator top hose connection to the engine?? your engine could have air trapped in the system. it looks like a square 6mm bolt that can be opened slightly and run the engine. pour coolant in radiator when coolant drops till you see some coolant start to come out of small bolt. fasten bolt when it flows out. i cannot find a pic of your engine so i'm blindly guessing at the cause. are the fans kicking on at full blast on the radiator?