Get the laser temp gun.

Get real world temperatures from the different parts of the system as suggested above.

Report back with numbers.

That is the proper way to diagnose the issue.

Without actual numbers the only thing ANYONE can do is guess. Some guesses will be right. Some will be wrong. You are nearly guaranteed to waste time chasing your tail.

We are brothers and sisters doing time on the planet for better or worse. I'll take the better, if you don't mind.
- Stu Harmon