Thanks for the tips… I am to the point where I am asking a lot of “is this normal” questions because I really want to run an engine, but feel like I have to make this tar cracking temp measurement first. Was hoping to profile the chamber temps at full blast then see what happens when I back the flow down really low.
I went outside for a bit of time on the gassifier tonight and tried the chamber temp measurement. I had some issues with a packed char bed, since this is the most char I have left in it a day or two and we had rain overnight so I am sure some moisture was absorbed in the char and that may have been causing me some packing problems. Tonight was the first night ever that I could not get it to flare. Just was not happening… I was able to measure up to 1400F in the burn chamber near a nozzle for what that is worth, but as I said, it was not flaring properly so I am hoping that it is running a bit hotter than that. The external temps were about 100 degrees lower than I measured on the last run, so I am sure it has to be hotter than 1400F when it is cranked up.
I put a cutoff wheel in between the SS probe cover and the conduit metal connector housing to protect it. It remained cool to the touch as long as there was fuel to cover the hot charcoal. Anyways, I will clean it all out, dry the char and try again to see what temps this thing is running.
BTW… how hot is “too hot” above the grate or below the nozzles ? Have you noted any temps just before something goes bad ? Honestly, I have been looking for failure points on this setup and am not sure how close to the edge it may be running.