Hi all, I am trying to fettle my Primus no.1 from 1911, with roarer head pictured below. There seemed to be nothing wrong with it except for an ugly yellow flame and a pulsating gas flow. I then cleaned the 100 years worth of carbon from the vapourising tube using the heat quench method. Fired her up, gas flow fine but flame still yellow. 'Maybe it is the nipple?', I thought, so off it came and I tried to switch it with a nipple from my Primus no.1 S:or silent burner (1934). To my surprise the nipple won't screw on. I then compared threads: The nipple from the old roarer is on the right and it can be seem it has a smaller width on the thread compared to the 1934 silent burner nipple. I then put the 1911 roarer nipple on the no. 1 S:or burner and lit her up. What did I see? A yellow flame from a burner that usually has a healthy blue flame. I figured it must be the aperture size: Again the nipple from my 1911 roarer stove is on the right and clearly has a larger aperture. My questions are: What am I to do about this persistent yellow flame? Is it the aperture size? Or do roarer nipples have a larger aperture than the silent burner nipples? Also if it is the nipple that needs replacing, how am I to be sure it will even fit, as my other nipple would not? Do I even need a new nipple? Or is it just that I need to clean the old tubes out more?
Yes, the jet aperture is enlarged. Do a search on how to make it smaller or order one from basecamp. The original thread seems to be tapered. Ron
