Wood won’t combust

[taffenhoffsbbq]

Hey guys, I’m trying to get my okj longhorn dialed in for the summer. I know it’s a COS but I’ve put some mods in it to help it out a bit. I extended the smoke stack, lowered the smoke collector to grate level, added a layer of fire brick in the cook chamber and fire box, and I have a baffle in the cook chamber as well. I’ve reduced the size of my splits (maple) to about 8” long and 2”ish in diameter. I can raise the splits off the fire brick about 1” with a cheap charcoal grate but that still doesn’t help. The only thing I can think of next is putting a fan pointing at the firebox to help airflow. Has anyone tried this? Thanks you guys, I’m flustered as hell.

[scottranda]

Do you have a moisture meter? Could be wetter wood.

[Johnny Booth]

Gotta have max airflow and wood must be less than 20% moisture. A good coal bed is essential to keep temps stable and light the next split. Hard to burn sticks in a COS, I used to have one. Same mods pretty much. Let the heat leak. It’s less efficient, but if you get sticks burning well with a good coal-bed it might want to burn a little hot.

[scottranda]

How do you light it? With a match? Charcoal chimney lit charcoal? Perhaps a propane torch helps get a super hot but maybe smaller fire going?

[taffenhoffsbbq]

Today I used the tinder from cutting down the splits, but I usually use briquettes. I’m thinking of buying cheap charcoal briquettes and using those throughout the cook. Add in a fan 6ish feet away from the firebox and I hope that’ll be just what I need to solve this problem.

[Lynn Dollar]

You say you " lowered the smoke collector to grate level " , how did you do this ? If you bought the mod I've seen some use, that thing is very restrictive to air flow.

And if you used some kind of duct, the heat/air has to take two 90* turns to exit the cook chamber.

A fella in another forum rebuilt the entire stack end by adding a real collector and new stack. He had the same problem, getting splits to ignite. He was using a mod that he bought that bolted on to the inside of the cook chamber.

Depending upon difficulty of removing what you've done, you could take it off and see if it helps the air flow.

The baffle will also restrict air flow. And if you're exhausting at grate level, a baffle is not a good thing. Depending upon the kind of baffle you're using, but if its the convection plate type, then you need to exhaust out the top. That's a bottom up cooker.

Here's the mod that reduces air flow

https://bbqsmokermods.com/lavalockr-smoke-stack-lowering-kit-for-oklahoma-joe-s-highland.html

[Johnny Booth]

Lynn Dollar - that analysis brings a lot together for me. I don’t have the COS anymore, but everything you said makes perfect sense. Wish I had it back now so I could re-jigger it again. 🙂

[Lynn Dollar]

I had an Old Country Brazos that exhausted at grate level and had a baffle. If I opened up the firebox too much, and got to much air flow, the heat/air would flow under the baffle, then under the meats, then right out the exhaust. I would get burned bottoms on the meats. Had to cut the air flow down.

Yoder and Horizon have not changed their design as bottom up smokers, even with everyone copying the Franklin collector at grate level. Nothing wrong with bottom up. They use a baffle.

[taffenhoffsbbq]

Next step for me will be to remove smoke collector and leave the baffle. I’ll check airflow then. Thanks very much, guys!

[mrteddyprincess]

I cook on a Lang offset, but I started out on a modified COS just like you and I got pretty good at using it to turn out tasty food.

I used a new charcoal chimney about every hour to keep it up to temp, and yes, I used a box fan to blow into the firebox. I would angle the fan to regulate the temps I wanted to cook at. I was throwing on wood chunks for smoke, but charcoal briquettes were my real heat source.

Good luck and don't give up! Feel free to message me if you run into other issues.

Brian

[Uncle Bob]

Without seeing what mods you've done it's difficult for anyone to give you meaningful advice no matter how well intentioned. In a way fire is pretty simple; enough fuel, enough heat to vaporize the wood cells, and air to help feed the fire.

Offsets are an induced draft system, in other words, the exhaust flow needs to draw the air in at the intake end in order to support the fire. If your solution is to blow air (forced draft system) in with a fan then you have an exhaust problem somewhere in the system. Alternatively, you may not be building your initial coal bed correctly, which is essential for an offset. Once a good coal bed is established you just need to feed it enough fuel to keep it going. Using splinters from splitting process likely isn't enough fuel to built a good coal bed. Adding briquets can work, but lump charcoal would be better as they function more like the burnt splits as the fire progresses. Either fuel though needs to be a healthy coal bed to get the process going.

[taffenhoffsbbq]

Thank you! It may be the smoke collector mod that I installed. Next test I’ll establish a bigger coal bed, and I’ll add some pictures too. Thanks again!

[Stuey1515]

This

[bmillin]

Hey guys, I’m trying to get my okj longhorn dialed in for the summer. I know it’s a COS but I’ve put some mods in it to help it out a bit. I extended the smoke stack, lowered the smoke collector to grate level, added a layer of fire brick in the cook chamber and fire box, and I have a baffle in the cook chamber as well. I’ve reduced the size of my splits (maple) to about 8” long and 2”ish in diameter. I can raise the splits off the fire brick about 1” with a cheap charcoal grate but that still doesn’t help. The only thing I can think of next is putting a fan pointing at the firebox to help airflow. Has anyone tried this? Thanks you guys, I’m flustered as hell.

Maybe try it without so much firebrick. I think a lot of your energy might be going into heating the bricks more than the fuel.

[Johnny Booth]

The more space you have for air to flow and mix, better off you are. If the bricks impede airflow. I would try it without them.

[taffenhoffsbbq]

Fellas, I think you fixed it! I took off the smoke collector mod and it’s getting better airflow. However, it happens to be a breezy day today so I’ll have to try another test on a more calm day. Thanks again!

[Lynn Dollar]

I think you've found the problem, the wind may've been a factor but only if the firebox was pointed directly into a stiff breeze. But I'm curious to see if that mod was the problem, for sure.