Trouble keeping temps up, help appreciated
 

So my last smoke, I had trouble keeping temps up.
The only changes I made to the pit (the CharGriller offset) were tightening up the air leaks, I attached some stove rope to the back where the base/lid had a huge gap, and put a bead of rtv on the firebox door to keep airflow coming only from behind the fire basket.

Had no problems at first, but after an hour or so my temps kept dropping, and I tried everything. Switching fuel (tried KB, wood, and lump), and all had the same problem. Next I added a 4 foot piece of leftover aluminum vent from the chimney mod to the outside to raise the stack in the hopes of more draw, which did seem to help a bit, but still had trouble.

The only thing that really seemed to help more was dumping the ash pan, even thought there was at least an inch or an inch and a half under the bottom of the basket at the time. And early on this could not have been my problem.

So can charcoal get ruined if it is humid out? It is MN and we get pretty humid here in the spring and summer. Coal is stored in the garage now.

Any help appreciated, want to do more butts, but need to figure out what I am doing wrong.

Thanks!

***Disclaimer: I am NO expert***

In my experience, air leaks cause temps to be too high, not low.

Low temps indicate a draw/intake problem- not enough oxygen to feed the fire. I'm not familiar with CharGrillers, but maybe check to make sure nothing is interfering with your intakes or exhaust. Ash build-up MAY be the issue if your temps are ok at the start of the cook (less ash in the pan) but drop off later as the ash builds up.

I've never heard of charcoal going bad unless the bag got totally soaked thru and coals got wet directly. Humidity is pretty much kept out by the paper bags the coals come in. Condensation is a different story, but there would be other evidence if that was the case, ie. moldy or crumbly/moist briquettes.

Plus, as the cook goes on, any humidity/moisture should evaporate out from the heat of the fire as time goes on. This would make your temps get higher as time goes on but probably not by much if at all.

That's my .02, hope it helps. I'm sure others will have more info for ya. Hope you get it figured out.

Open the exhaust wide open

Sounds like you have a handle on your leaks. My first question is what is your fire basket made of and how big is it? 2nd Q have you taken a dryer duct and run a length of it to grate level from the exhaust? 3rd Q how many briquets do you light when starting your fire? From this i think we can help some more.

Exhaust and intake were both wide open when having issues, on prior cooks, to keep 225ish I had exhaust wide and intake at 25% or so. Fire basket is the wire one that many used to mod this grill, stainless steel (pic: http://tinyurl.com/79n4r9v )
Yep, ran the vent to grate level. Butt was kinda close to it but not blocking it.
I lit maybe a dozen or less, placed lit coals in basket away from the intake to slow the burn, which has worked great in the past.

Thanks again.

Was it windy out on a thinner smoker the wind can be a killer.

This is how I modded mine and it holds temp very good and has a 7 deg temp spread across the entire surface.
1. extend the exhaust stack on the inside down to 1" above the grate. I rolled up some aluminium flashing and stuffed it into the pipe.
http://i968.photobucket.com/albums/a...G/PHOT0060.jpg

2.Remove the CI grates from the fire box and put 1 at each end of the pit and turn the Charcoal pan upside down and put it on top. Push it all the way down to the fire box so it contacts the side.
http://i968.photobucket.com/albums/a...G/PHOT0194.jpg

3. Build a log rack;cut some 1" angle iron 12.5" long and lay them in the fire box, use a 12X24" piece of expanded metal bend it at 4" on 1 end and 2 " on the other and put it on top of the angle iron Put the 4" side to the fire box
http://i968.photobucket.com/albums/a...G/DSCN0597.jpg

Another place you will loose heat is around the lid the way the hinge is assembled it won't let the lid close in the same place every time so I shinned the hinges with some flat washers and made a gasket from aluminium foil to seal the top.
http://i968.photobucket.com/albums/a...G/PHOT0195.jpg
http://i968.photobucket.com/albums/a...G/PHOT0061.jpg

I start with 1 whole lit chimney of lump and 2 splits and feed 1 split every 45-1 hr I preheat my splits on top of the fire box. exhaust full open and the intake at 1/4 open it will run 250 without a problem.