Overheating 2001 infiniti qx4

[volvera666]

Hello community.

I have a specific problem with my 2001 Infiniti Qx4 4WD suv, it is overheating in minutes!!!

I did the service on the cooling system last weekend, flashing with water and air and replacing the cooling for a brand new and I found just some corrosion but I cleaned it up. I spent few hours checking everything but couldn't find any damages that can lead me to the overheating problem.
No leaks
Radiator okay
Upper and lower hoses replaced by brand new ones
New Thermostat (I install a new one because the last mechanic removed it )
Water pump okay

But my car still overheating
I have no idea what to do next

Please any suggestion will be very welcome

By the way:

I am not a mechanic, I had a really bad experienced with a mechanic couple years ago and since then a prefer do it myself, no offence but I don't trust mechanics anymore

Thanks

PD: Please help, it is urgent, this is my daily car.

[fleurys]

Put your truck on an incline so that the radiator cap is higher than anything else on the engine (you can use ramps if you have them or else park in an incline terrain). remove radiator cap, start the truck. Let the bubbles come out, put more coolant if it needs it.

While doing this, keep an eye on the temp to make sure it stays within safe specs. If it does not, then you are not inclined enough.

Let it run until coolant is coming back out. put the radiator cap..

Do this with good leather gloves or protection as it will be very hot near the end.. That's how I got rid of my overheating problem on my own 2001 ..