Doing a coolant drain & fill, I opened the petcock at the bottom of the radiator, and also turned open a similar-shaped valve towards the top of the radiator (a video said to do this, to release more air).
Now I'm closing everything up and getting ready to add coolant---at what point in the process do I close this valve--before pouring in the coolant, or after it is burped?
Now I'm closing everything up and getting ready to add coolant---at what point in the process do I close this valve--before pouring in the coolant, or after it is burped?