I am using a propane turkey fryer burner with a Cast Iron plate/lid on the top to hold my smoking wood. I am using hickory chunks and it seems that they smoke for about an hour (if that) then they turn all black and quit producing smoke. The last stuff I smoked didn't have a very smoky flavor. I have around 12 holes drilled in the lit of the pot do I need more? The holes are pretty small. It just seems like they should smoke a lot longer than they are and they should turn to ash not just black pieces of wood. I may try lifting the lid off or just move it to the side a bit to give it more air. What do you guys thing?