Jeff,
I’m a convert to lump also. One of the beauties is that it can be put cold on top of your hot coals when you need to re-stoke your fire. If you’re on the ball, you’ll be able to sense when to add fresh lump before the old is used up and the temp will hold steady throughout. In the winter, I usually have some lump going in a second burn barrel to add at any time, as well as to put out some heat. It can get pretty cold in my north-facing garage!
I’ve taken Jim’s idea one step farther and put a sheet of perforated aluminum over the charcoal grate. Before each cook, I pick the whole works up and give it a few shakes. The aluminum acts like a screed to sift out the ash and pieces of lump too small to contribute to the party.
Before starting a cook, I also mix the old lump throughout the new rather than just dump the new on top. I’ve found the old, smaller pieces of lump can form a relatively dense layer at the bottom of the charcoal ring. As ashes from the new lump accumulate, the old fuel can be slow to burn and causes the temp to drop once the new stuff has given its all. I believe the fire "breathes" a little more evenly this way over the hours. That’s been my experience, anyway. Of course, YMMV.
Like Jim said, when the cook is finished, close all the vents and the lump will soon be extinguished and ready for next time.
Enjoy your Easter weekend. I’ll be on the road so I won’t be getting any WSM therapy. 8(
Ken
