Why instead of a torch flame i have a regalur light flame?

If this is a Gas jet torch lighter it probably doesn't have one. It uses an 'electronic' ignition which doesn't need a flint. These "piezoelectric' lighters can last for 10 or more years with no problems.
If it is working correctly you should hear a 'click' when you press the button. Gas 'torch' lighters tend to run out of gas more often as the flame burns more fuel at a faster rate to produce the 'Jet' flame. If it isn't lighting properly try refilling it first. These are generally considered a 'cheap' lighter so if refilling doesn't help you could just buy a new one.

try cleaning pilot generator or replace if low flame will not lite

YOU CAN BUY A NEW HEAD ONLY AT THE HARDWARE STORE.

Too much gas! Turn it down and check that nothing is blocking the airways.

Get rid of the flash backs, you are working with low pressure and the will give you problems. Plus with what you are doing they are not needed

Is the flame you are getting a carbonising flame? ie. is there a lot of soot in the flame? It sounds like your oxygen regulator is faulty and not regulating, blowing out your flame as soon as you open the oxygen bottle. The acetylene side seems to be ok but have the oxygen regulator overhauled.

sounds like your needle valves are worn or damaged,also change allthe q rings in same valves

Is this torch powered by acetylen and if so then the yellow gunk you are seeing is unstable acetyleen which is caused by a torch that is releasing the gas faster then it can be handled in normal atmospher whic would be why you can not get a blue flame, I would say that the tip is to large for the tanks you have the system attached to. I would ask your dealer to suggest the tip size that the torch set you are using would be compatiable with the tank size you have attached. I would not try to use the set until I get it sorted out as unstable acetyleen is very explosive. Hope This Helps Don