ditto on kate's comment. I have the same set up, but usually my juice has a bit of vg, pg is very runny. Seems 95% of my leaks came from too little filler, or poorly positioned filler (I use the adm mod with fluval). Once I got the right amount of filler I haven't had a leak. Also, because I too fill them up a little too much, as soon as I get the freshly filled cart assembled I take a few quick drags with the unit pointing slightly upwards. Not sure if it does anything, frankly, but I figure if I can get that first ml or so vaped up it should prevent excess. I think the proof is in the pudding: since "getting it right" I leave my ego sitting with the cart in the air, on the flat top of the battery over night, and between vaping. I still haven't had a leak or flooded atomizer since.