yeah i had that problem too when i started with my 801. then i learned how to fix it. if u r dead set on using carts, when u top off ur cart, make sure to squeeze the walls, when u think u have enough juice in there to last u a while, squeeze ur bottle of juice and the cart simultaneously to form a puddle of juice on top of the cart, then dip the tip of ur bottle in the puddle and suck up the excess. then squeeze the cart one more time to get the juice worked down deep into the cart fibers. without replacing the cart take a pull or two on ur PV to burn any puddles of juice around the coil/ bridge and then replace the cart. this method worked well for me, to keep it from leaking. then again u could always just start dripping, like i do now, the flavor is much more intense and the vapor is too. good luck