Bill,
Haven't received any pm's from you in a while.
Glad you got her up and smoke free. I guess we are pretty fortunate here in MI. We seem able to be able to just put wood in and go. Taking a couple gravel shovel fulls of fine ash out of the primary burn chamber every three or four days and keeping the nozzle area relatively clear seems to be the ticket for us.
My air box looked as clean as it was the time I had opened it up last. I had to take the cover off to install my top secret mods a few weeks ago
I'll bet if you keep everything hot you'll not have an issue again. Today I'm going to try and get the Carquest part # for the screws I used to replace the old self tappers and share it with you all.
I wouldn't be worried about the nozzle opening at all if I were you. I believe that area in the refractory is about 4" thick, and as long as we don't just throw heavy pieces of wood in, they will last for a long time. I'll bet several years. If you look in the secondary burn chamber at night you'll see there is no chipping or cracking on the bottom side of it.
I am deliberately treating mine worse than I should to give myself an excuse to replace it. I have a $100.00 bag of 3200 degree refractory cement just waiting to get mixed up to form a new nozzle. Hope the P&M guys don't read here!
AND....Just so you know, I'm learning just as much from you as you are from me. I like to talk, but I actually listen to what I'm hearing. Thank You!
Marty