WSM 18" coal burn time

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Turkeyyum

Newbie
Original poster
Mar 10, 2024
4
5
Hi all, I'm a rookie smoker and I've slowly been working my way through the different meats and things to smoke and I've had this reoccurring issue. Usually after around 6-7 hours of smoking time in my WSM the temp starts dropping and I can only keep it going by continuously stoking the coals. I hear people say that they can get 12+ hours of cook time on WSM's and I'm just wondering if there's something I'm missing.​
  1. I use Kingsford blue original briquettes and I start by putting around 12-15 coals into the chimney and I light them with some newspapers. While they are heating up I fill the coal ring pretty much to the top with a little crater in the middle for the coals.​
  2. I use around 3 fist sized chunks of wood or approximately that amount in chips if there's no more big pieces left. Once the coals are lit I dump them in, put the torso on and fill 3/4 of the water pan with water. After I just put the lid on and make sure all vents are wide open until it approaches around 200° and then I close down all 3 bottom vents until around a pencil width which is what I hear a lot on videos and such.​
  3. Then I do some waiting and a bit of tweaking until I get it to stay stable around 225° and I add my meat. I check the thermometer 1-2 times an hour just to see if the temp is still stable.​
  4. Usually around 3-4 hours in I check on the meat and move the coals around a bit to shake some ash off. Everything stays fine until around the 6 hour mark where the temp starts dropping and I see that there's not many coals left in the ring. I end up stoking the coals every now and then just to keep them going for as long as I can. Eventually I take out the meat and finish it in the oven.​
This has happened twice now. Once in August on a windless day and just recently on a colder windier day. I tried to compensate by putting the WSM in a semi surrounded area with some cardboard near the bottom vents to block the wind. I live in Toronto which is usually a pretty humid place. I would appreciate any advice on things I can try or anything I might be doing wrong and I'm happy to provide any more information if its needed.​
 
Welcome to SMF!

Couple thoughts:
*look here if you haven’t. https://www.virtualweberbullet.com/.
*You may like the minion method. It will last much longer and be a more controlled burn.
*I eventually ditched the water for a dry foil lined pan. The water sucks a lot of heat out. It’s used to control the temp, but sounds like you are on track for temp control. You should be able to manage the temps the same.

Minion and no water in the bowl should get you much more time.
 
Lots of great information in the link above, though you have to go through it.
how you gauge cook temps can vary greatly. If you're depending on the stock gauge in the lid of the WSM, you maybe getting inaccurate information as to actual chamber temps. This is slightly off topic, but if you want to know what temp your meat is cooking at, here's what I do.
I use an Inkbird Inkbird i-BBQ-4-t 4 probe thermometer, but that's another topic altogether. I typically feed two probes thru the grommet. one for the meat, and the other I hang upside down, midway between the meat and the side of the grate (see pic). Remember the chamber temps will be higher towards the outside edge of the chamber cylinder. My cook last weekend was 12-13 hours for an 8lb pork butt, with B&B charcoal (another discussion). Filled ring almost to top as you described, using a minion type method. Cooking temps might take awhile to hit your target.
about the 10 hr mark I did "stir" the coals to knock off any ash. I ran pretty close to 230-ish the entire cook. Around hour 12-13 I think i was running low on fuel and added 10-12 briquettes to maintain 230. Sorry such long gibberish.


temp probe.jpg
 
Welcome to the forum Turk, glad you joined us.
What you described sounds like my experience as well. Smoking chicken, turkey and ribs I would have plenty of coals but large pork butts and brisket, more than about six hours, I always had to add coals. It just became part of my process. sandyut sandyut 's post should help you out a lot. When I started smoking it was with a WSM 18 that I got for a Fathers Day gift and TVWB was a huge help.
Again, welcome and enjoy your stay.
 
Welcome to the forum Turk, glad you joined us.
What you described sounds like my experience as well. Smoking chicken, turkey and ribs I would have plenty of coals but large pork butts and brisket, more than about six hours, I always had to add coals. It just became part of my process. sandyut sandyut 's post should help you out a lot. When I started smoking it was with a WSM 18 that I got for a Fathers Day gift and TVWB was a huge help.
Again, welcome and enjoy your stay.
I was able to keep my 14.5 going for 8-10 hours without adding coals. Once I added a controller, I get even more time.
 
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You seem to be doing everything correct, and are using a minion method.

The only thing you really haven't talked about is how much you are filling up the charcoal area in the WSM. You want that thing brim full.

Don't be afraid to use more wood chunks for long cooks. Too many people are scared of over smoking, but honestly, for a 6-8 hour cook, I've used as much as 1 chunk per hour and still didn't find it oversmoked. That's a seperate topic, though.

My guess is that you are not brim-filling it. You pretty much want to BARELY be able to set the water pan on top of it.

Also, I've never used Kingsford blue much. Try using B&B Charcoal which is what I use. Take a look at this burn test:
 
Welcome to SMF!

Couple thoughts:
*look here if you haven’t. https://www.virtualweberbullet.com/.
*You may like the minion method. It will last much longer and be a more controlled burn.
*I eventually ditched the water for a dry foil lined pan. The water sucks a lot of heat out. It’s used to control the temp, but sounds like you are on track for temp control. You should be able to manage the temps the same.

Minion and no water in the bowl should get you much more time.
Correct me if I'm wrong but I believe what I do is the minion method. I fill up the chamber with coals and then I dump around 12 lit coals on top of the unlit. I have tried not using the water pan once before and I struggled to keep the temp below 275 but I can try again and see what it does for a longer burn time.
 
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Lots of great information in the link above, though you have to go through it.
how you gauge cook temps can vary greatly. If you're depending on the stock gauge in the lid of the WSM, you maybe getting inaccurate information as to actual chamber temps. This is slightly off topic, but if you want to know what temp your meat is cooking at, here's what I do.
I use an Inkbird Inkbird i-BBQ-4-t 4 probe thermometer, but that's another topic altogether. I typically feed two probes thru the grommet. one for the meat, and the other I hang upside down, midway between the meat and the side of the grate (see pic). Remember the chamber temps will be higher towards the outside edge of the chamber cylinder. My cook last weekend was 12-13 hours for an 8lb pork butt, with B&B charcoal (another discussion). Filled ring almost to top as you described, using a minion type method. Cooking temps might take awhile to hit your target.
about the 10 hr mark I did "stir" the coals to knock off any ash. I ran pretty close to 230-ish the entire cook. Around hour 12-13 I think i was running low on fuel and added 10-12 briquettes to maintain 230. Sorry such long gibberish.


View attachment 691245
I'm here to learn and listen so its not gibberish at all. I have heard the stock temp gauge is not very exact so I purchased a Thermoworks Smoke thermometer. I run an ambient probe under the lid and I try to put it under the small handles that are on the sides of the top grate to avoid things like grease falling on the probe and messing with the temps. I so far have mostly only used Kingsford blue because its readily available for me and I've heard that the WSM was designed using it. I will try to find B&B and try it out.
 
You seem to be doing everything correct, and are using a minion method.

The only thing you really haven't talked about is how much you are filling up the charcoal area in the WSM. You want that thing brim full.

Don't be afraid to use more wood chunks for long cooks. Too many people are scared of over smoking, but honestly, for a 6-8 hour cook, I've used as much as 1 chunk per hour and still didn't find it oversmoked. That's a seperate topic, though.

My guess is that you are not brim-filling it. You pretty much want to BARELY be able to set the water pan on top of it.

Also, I've never used Kingsford blue much. Try using B&B Charcoal which is what I use. Take a look at this burn test:
I fill it up to the brim but leave a small divot in the middle for the lit coals. Should I be filling the chamber completely and then dumping the lit coals on top of them?
 
I fill it up to the brim but leave a small divot in the middle for the lit coals. Should I be filling the chamber completely and then dumping the lit coals on top of them?

Naw, you're doing it right. Leave a devit in the center (as best you can). Just make sure you have charcoal surrounding it that's so full that it's just about to fall over the edges.

IMO, try B&B charcoal your next go around. You should have no problem doing 8+ hours for those!
 
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I can only speak from using the 14.5" WSM.I take a soup can and put in the middle and stack my briquettes as uniformly as possible around the can (with a few wood chunks mixed in),then dump about 1/2 dozen lit briquettes into the can and then remove the can.And yes you need to remove both ends from the can,people have asked.
 
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I recently did a brisket flat using the minion method. Almost totally full charcoal ring, no water pan. It ran at 275 for nine hours before the temp started to drop.
 
Hello. I am new here, but started on and still have an 18.5 WSM. I find going to B&B orange bag briquettes will extend your cook time as they burn slower. A couple of other things to do. I bought a second grate and turned it 90 degrees to the other charcoal grate to create smaller holes and keep the burning charcoal up on the grates. Second, I use a coffee can in the middle of the charcoal grate, then put down my smoking wood, fill around the coffee can with briquettes up to the top. Then I start charcoal and dump in the empty coffee can and then pull the can and that is the perfect minion method starter. I have gotten near 12 hours on B&B in 20 degree weather overnight with that setup at 225 to 250.
 
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