If the tank is getting really hot, you need to deal with that first. Try either running it at a lower power, or drawing more air through when you fire it. (Also, releasing the fire-button a second before you stop inhaling can help a lot).
If the head heats up, this will cause the air in the tank to expand, and the pressure is going to force more e-liquid down onto the coil.
Unlike some other dripper-tanks (where there is actually a seal that closes when you're not pumping) the big dripper relies on air pressure to keep the liquid in the tank, rather than having it drip through the hole.