I have probably fettled and resold/given away over thirty Shinabro 340s (I used to buy them in bulk from Scout troops), but I have never had one with a leaky burner until now. Next to the small Monitors this is probably my favorite stove, mainly because they are cheap and (usually) very well made - and the cases are bullet proof. This was a relatively unused stove and the burner was in good condition, except the flame had yellow tips. After closing the jet slightly to 0.28mm the problem still existed, except now there were only two yellow tip areas instead of four. These two yellow flame areas were diametrically opposite each other wrapping around the vaporisation tubes. Had it been one area of yellow flame I would have suspected a leak, but two areas still suggested either the jet size or grease/salts contaminating these two burner areas. After a thorough clean and a nipple replacement there was no improvement. I leak checked the burner using a rubber washer/ spring arrangement over the nipple hole, and connected it to an air bed foot pump. Sure enough two very small streams of bubbles appeared from the top of the two burner tubes when the pressurised burner was immersed in water. A quick braze on each and the burner works fine now with a nice blue flame. I suppose even Shinabro employees had bad days, but this is the first time I have had a problem with a Shinabro burner. If you have one, don't forget that the burner-to-riser joint (which secures the primer cup) is a left hand thread.