I copied this post awhile back. Should help. Seems it could be a weather thing or to save on fuel. Die hard smokers keep it in the smoker until done. At about 140 degree's the meat stops taking in the smoke flavor, so at that point it's just cooking. It's up to you.
Hope this helps! Jer
Basic Pulled Pork Smoke
Iâ€™ve been reading a lot of posts from newer members asking questions on how to smoke a butt or picnic for pulled pork. The Mods have made this a â€œStickyâ€.
Please feel free to add comments or additions to procedures described here that you use, like tips and tricks of the trade.
Choice of meat:
I use bone in Pork Shoulder â€“ Boston Butt for my pulled pork. They range from 5 to 9 pounds. I find mine at Samâ€™s club cryo-packed with two butts per pack. Sometimes you can find them in supermarkets, or if you have a source at a meat wholesaler you can get them there. Some folks use a fresh pork picnic which is the Butt (Shoulder) and the upper front leg bone together. They are larger than the Butt alone.
About 12 hours before the meat goes in the smoker, trim a little if desired (I usually donâ€™t), apply a coating of your rub of choice, and wrap in plastic wrap and put it in the fridge. (Some folks put on a coat of yellow mustard before the rub to hold the rub on and add to the bark. The mustard taste cooks out. This is a matter of personal preference.)
I canâ€™t give instructions for each type of smoker, as I have experience only with mine. (GOSM and CharGriller w/ SFB) Check the forums for that info.
Start your smoker and get it up to 225-240 degrees F. My personal wood choice for pork is hickory. Unwrap the meat, stick in the probe of your digital thermo (A highly recommended accessory.), and place the meat in the smoker, fat side down. I don't flip butts as it interferes with bark formation. Fat side down helps protect the meat if you have a temp spike. After the meat gets over 100F I spray it every hour with a 3 to 1 mix of apple juice and Captain Morganâ€™s Original spiced rum. I have used bourbon instead of rum, but my family prefers the taste of the rum spray. The sugars in the juice and booze will caramelize, and add to the bark. (Bark - dark outer crust that develop as the meat cooks.) Others will make good suggestions for alternate sprays. You will develop your own favorite with a little experimentation. (The nice thing is that they all taste good!)
When the meat gets to about 165F, double wrap it in Heavy Duty aluminum foil. Put some of your spray of choice in the foil to help braise the meat. At this point I usually stop making smoke unless there are other things in the smoker that need the smoke. (You can finish cooking from this point on in the oven set at 250F if the weather changes or you want to save smoker fuel.) Continue to cook until the internal meat temps gets to 195-205F. Remove the foiled meat from the cooker and wrap it (still foiled) in a couple old bath towels and put it in an insulated cooler to rest for at least an hour before you pull it.
Almost all butts (and briskets â€“ but thatâ€™s in the beef forum) will hit a plateau where the temps of the meat stops rising. Donâ€™t be tempted to raise the heat as that will dry out the meat. The meat is absorbing a lot of heat at this point while the connective tissue is breaking down. This is what makes the meat tender. Low and slow is the way to go! Iâ€™ve seen some actually drop in temp by a couple degrees. Patience â€“ it may be over an hour before the temp starts climbing.
There are several choices here, some folks use two forks, there is a tool called bear claws, Dutch puts hunks of it in his Mixmaster with the dough blade to pull. I use my hands. I un-foil the meat, the bone usually falls out on itâ€™s own, and I break it apart in to big pieces that I let cool for a few minutes. I then go through each piece and pull out the extra gunk (technical term for fat and connective tissue) and shred by hand.
I serve my pulled pork with my sauce(s) of choice on the side. I will add some of SoFlaQuers finishing sauce (another sticky here in the pork forum) to the pork just after Iâ€™ve shredded it. My personal favorite way to eat it is on a cheap white bun (CWB) with a little BBQ slaw right on the pork in the sandwich.
Time of smoke:
The general rule of thumb is that it will take about 1.5 hours of cooking at 225-240F per pound. Keep in mind that this is just a guideline as each piece of meat is different. Go by temp not time to know when it's done. Someone here said, "The meat will be done in it's own good time." I once had two 8 pound butts finish an hour apart in time. Give yourself extra time, you can always keep it wrapped in the cooler a little bit longer before you have to serve. It's hard to rush a piece of meat if it does not want to be done.