Today I fired up my 18" WSM for the second time (tried to make brisket a week ago to mixed results) in an attempt to smoke a pork butt. I had some temperature issues throughout the cook that have left me with a few questions, but when it was all said and done I had some tasty pulled pork to eat so it worked out in the end. Here's a quick recap of the cook with pictures:
I purchased a 4 lb Boston butt from the local grocer:
I trimmed the fat from the bottom and some other bits here and there before applying the rub, which I did 12 hours before the actual cooking:
I started my WSM by filling the charcoal ring with unlit K and some hickory chunks and apple chips, then placed about 20 lit coals on top in the middle. The temperature here in Columbus was about 35 degrees, so I initially opted to leave the water pan empty. But after the first hour, the lid temeprature was reading ~260 degrees (and rising) so I filled up the water pan - was that a reasonable thing to do?
After 4.5 hours, I placed a remote thermometer into the pork butt and the temperature read 165. I expected 6-8 hours to cook this 4 lb butt so that seemed ok. What has me confounded is over the last 2.5 hours of the 8 hour cook, the temperature quickly got up to about 176 degrees and then plateaued. (I had other things to do today so I had to pull it after 8 hours even though the temperature still read 176.) I know that there are plateaus when cooking meats, but this seemed wrong to me? The lid thermometer read between 210-225 during this entire time.
Anyway, here is the butt after I took it out of the smoker and foiled it for 30 minutes.
And here is the final product after pulling. It was a little tougher to pull than expected, but it it tasted good and was not overly chewy so at least I had that going for me.
If anyone has any thoughts on why the 4 lb pork butt was locked in at 176 degrees from hour 5.5 to hour 8 of the cook despite the lid reading staying in the 210-225 range, I would love to hear them. Thanks for reading!
I purchased a 4 lb Boston butt from the local grocer:

I trimmed the fat from the bottom and some other bits here and there before applying the rub, which I did 12 hours before the actual cooking:

I started my WSM by filling the charcoal ring with unlit K and some hickory chunks and apple chips, then placed about 20 lit coals on top in the middle. The temperature here in Columbus was about 35 degrees, so I initially opted to leave the water pan empty. But after the first hour, the lid temeprature was reading ~260 degrees (and rising) so I filled up the water pan - was that a reasonable thing to do?
After 4.5 hours, I placed a remote thermometer into the pork butt and the temperature read 165. I expected 6-8 hours to cook this 4 lb butt so that seemed ok. What has me confounded is over the last 2.5 hours of the 8 hour cook, the temperature quickly got up to about 176 degrees and then plateaued. (I had other things to do today so I had to pull it after 8 hours even though the temperature still read 176.) I know that there are plateaus when cooking meats, but this seemed wrong to me? The lid thermometer read between 210-225 during this entire time.


And here is the final product after pulling. It was a little tougher to pull than expected, but it it tasted good and was not overly chewy so at least I had that going for me.


If anyone has any thoughts on why the 4 lb pork butt was locked in at 176 degrees from hour 5.5 to hour 8 of the cook despite the lid reading staying in the 210-225 range, I would love to hear them. Thanks for reading!
