So this is my second week vaping and I just got my vamo v3 and protank in the mail. After messing with the replacement head I noticed e-juice on my battery post. I tried fixing it and for some reason when I tightened the head all the way into the base I had absolutely no air flow. I ended leaving the replacement head pretty loose and just got leaking. My final fix was to replace the stock o-ring on the head. The one that is on the threads that screw into the base. It is a little bigger than stock. This makes it so you can't screw the head in more than about 1 turn. The seal is good though. This also enables me to screw the base down completely into the vamo. You can check clearance by putting the base of the tank onto the vamo then putting the head in so you know how how far you can go down without pushing your positive battery pin down. Once you got that just take it off the vamo/mod and put it onto the tank as usual.This should create a good seal between the head and the base as well as the seal between the head and the airflow tube that goes into the mouthpiece.