Sorry long time since Ive responded, tackling the tank today, does this trick only work if I have a CSV? Thanks!
No that trick is to tell you if you have a brass or rubber bleeder. But if it is rubber and pops out, you will have to pull the pump and plug it. Bleeders only see high pressure, and even a rubber bleeder will work without a CSV. But the CSV makes more pressure on the bleeder so it must be a brass bleeder or just plugged.