UDS Temp Control Problems

[Girevik]

I did my first cook this weekend. It came out awesome (considering I bought the wrong cut of pork butt). I did have to babysit the temperature, a lot. When I did my seasoning burn earlier I had no problem controlling the temp. This time however the temp wouldn't stay put. I think it could be 2 different issues.

I leave the top vent wide open. The top vent is a round rotating thing like on a weber. It is made up of 8 x 3/4" holes. The smoker has 2 sets of slider vents on the bottom. There are 4 x 3/4" holes on each side. I really don't need that much intake. 1 vent on each side open leaves the temp over 300.

Issue # 1:
There is a slight leak around the lid. I probably need to put a some sort of rope/gasket there. Any suggestions? The lid came with a rubber/foam seal in the lid. I took that out fearing it would melt.

Issue # 2:
I don't think I had the coals done right. When I did my seasoning burn the coals burned down fairly evenly. The fire basket was lower all the way around. This time when it was all over and I looked there was a big deep hole down the center of the lump charcoal. I must not have spread the coals from the chimney starter well when I dumped them in there.

I have seen people mention putting things in the center of the coals - like a can, or even splits of wood. Do you think this would help for next time?

Thanks in advance for your replies.

[Girevik]

Update ...

I installed a gasket from BBQGaskets.com. That seemed to help. The temp was much more stable.