Hello, recently I have found an old blow torch in my dead grandfathers workshop. Its a turbo torch air/propane and Map pro brazing and soldering torch, hooked up to a propane tank. If it matters the tank size is larger than a hand held one but smaller than a 20LB, [very strange size]. But anyway it's a Manuel start but I'm having trouble starting it. I turn the gas valve a little bit and I strike it and it lights a huge fire ball all around the torch, burning my hand. Then it goes out. So I tried barely turning it at all and it lit and stayed at a very low flame. So I tried to slowly open more gas into it and it popped another fire ball and went out. I don't have any expirence with this specific torch but if anyone knows how to solve this, let me know please.