Just a thought- after the meat hits 140* internal temp, it's about done taking on smoke. If you are having trouble keeping temp, there's no shame in finishing it in the oven. BTDT.First smoke ever today-my neighbor gave me his Brinkmanns Smoke n Grill . I did some modifications- installed some vents and a hole for a real thermometer , not the one that came on the side of the smoker. Bought some apple wood chips and am using the recommended lump coals- Cowboy coals is the brand I believe . Tough to get keep thing up to temp with the pork butt on it , but once I did seems to be maintaining pretty good after 2 hours in . Updates to come .....