Ford au , te50 v8 coolant issue help please

[gencer]

Hi guys,

I have a te50 which Was handed down to me from family and I’m trying to diagnose the coolant boil issue.
After 10-15mins idle the coolant bottle will started to boil crazy.

What I’ve looked out for,
Seems like it’s got a new water pump (someone tried to fix it before)
I put a new thermostat and also tried with no thermostat
No oil mix (in water or oil)
When on idle at the start doesn’t seem to have air in the coolant system

And one have any ideas before I start taking the motor out for major head damage?

Thank you guys in advanced.