Thank You for this link. I was having the same issues with my T3S and Protank heads. Even looked at them with a 10 power loupe and could not see the leg glowing, but could hear the rubber squeeling and see smoke coming from the rubber.
I went crazy for about
three weeks messing with these things, and finally decided it wasn't worth my time anymore. I would like to give it another go with fresh grommets now