It is quite possible that the circulation is limited, if there is build up of rust or gunk inside water pathways the radiator could run at lightning speeds wouldnt cool that part of the engine as water isnt going there.
If head gasket is replaced just for the sake of avoiding the leak/mixing of oil&water then this is a half measure.
You need to check if the block has proper circulation, and water/coolant is going into all parts of the engine.
Use 1L vinegar mixed with 3L of water , see if it runs clean or becomes red/brown with rust. Hot vinegar dissolves all calcium deposits (which by the sound of it using normal water) eventually builds and blocks passage ways, use baking soda to neutralize later on. This is the cheap method.
Use Liqui Moly radiator flush and run it for a few days mixed with any cheap coolant.
Rinse and repeat.
A sealed cooling system which uses coolant will last atleast 5 years once its done properly, otherwise keep using water and lose the engine head gasket every few years
