VX overheating randomly...

[SMOTAN]

hey guys i got a quick q and my car seems to keep having this problem.
Randomly when im driving the car decides to overheat once a month its very rare,
but does my head in since ive changed the thermostat and radiator(radiators cracked once before)
and it was fine for a few months then started all over again the cars been like this since day one of owning it (ive owned it just over a year).
anyone have any ideas??

[SMOTAN]

btw its a v6 if that helps

[glowworm]

did you bleed the system ? maybe air is traped in it