Only a guess based on a SOB we owned a few years back.
If the flame turns yellow, that means that there is too much air being admitted through the slot in the air/gas tube. I my case I was able to do some bending and twisting of thar tube so that when the burner heated up, it wouldn't expand past a given point. That adjustment is somewhat similar to the air/gas tube on the HW heater - too much air, sooty yellow flame, too little, it sounds like a 747 in take off mode
Traveling with my DW Susan, a couple poodlepups and our 2014 Montana High Country 343RL, being towed by a 6.7 2011 F250 CCLB using a B&W hitch and OEM puck system