I BOUGHT A NEW SUNFLOWER LAST YEAR AND HAD THE SAME PROBLEM. COULD IT BE THE SMALL TANKS DON’T HAVE ENOUGH PRESSURE FOR THE LARGER HEATERS? I WILL FIRE UP MY BIG SUNFLOWER ON A BIG TANK AND SEE WHAT HAPPENS.
You may also want to try checking the themocouple (sp?). I had a heater that was doing that, and I found a small crack in the line. It did fix the problem once I got a new one.
Not 100% familiar with the Big buddy heaters, but I’ve heard they are prone to being blown out in the wind. Some people I think made little sheilds for the pilots. They also have a tip sensor in them that will turn them off if they get moved around too much or tipped over.