That such a friend
tells me that he heats up when he travels a certain kms and with the ac ignition.
I recommend you check that the 2 radiator fans properly work when the AC, that the radiator is not covered or dirty, water pump or thermostat, to check these lasts
with care not to burn you touches the two hoses of the radiator, if one is cold and another hot you bring water circulation problems, if the height persists, you can
take the posivility of the culata burst
.