digger104 wrote:in the evening around 10pm I bank the fire and close the draft
Like braindead says, probably not a deep enough coal bed, or too much ash. Try shaking down a LOT more, until you see some live coals drop, not just a few embers.
But what do you mean by "bank the fire"? I don't think it's quite the same thing to bank a coal fire, as to bank a wood fire.
Also, what do you mean by "close the draft"? You can reduce the air inlet, and you will have to experiment as to how much you can reduce it and still keep it burning. But to close it off completely, I don't think you can expect it to go all night on zero air. Perhaps the air inlet has an adjustable minimum that remains open even when you close it "completely"???? If so, you may need to adjust it to a higher minimum.
Good luck, and give us feedback on how it's going!