The quality of thermostats found in local auto parts retailers is very hit and miss. I recommend you purchase a thermostat at a Cummins parts store in order to save yourself some grief in the future.

 

Going to get a thermostat, but that brings another question....180* or 190* thermostat?? Which one and why?

 

This will help you a little getting the air out.

https://www.dieseltruckresource.com/...pump+shortcuts

 

I've always stayed with the 190. I can't see any reason to go lower. I only use Cummins stats. Not cheap but they are better. I tried a napa stat several years ago and the port was smaller and it hurt in the Co. mtns. Craig