I just used a lot of coal: first turn open the valves then put in some coal (3 or 4) then wait till the arrow falls back to the first stand (not laying flat, but 1 time to above; 10 'o clock) and put in 2 coal, let it fall back, again 2 coal that worked for me and if you run out of coal: go mine some in fally and come back: the tar won't disappear