bubble sound in valves

admin

We recently purchased a torch kit from Harbor Freight, Acetylene-Oxygen.  We use it to solder keys on music instruments.  We have a bubbling sound around the valves at the end of the hose closest to the welding tip.   We had it replaced and still get the same problem.  We cannt find any external leaks, by putting soap on the valves and looking for bubbles.  Any ideas
Reply:The valves right at the end of the hose where it connects to the torch?Those valves are probably flashback arresters/check valves and the sound is probably just the action of the back stop valve inside being lifted off its seat as the gas flows through them.I don't know if HF torches are prone to this or not, but I also can't recall ever hearing a flashback arrester/check valve being noisy either.  But then again, I have never used a Harbor Freight torch either.
Reply:They are the valves at the end of the hose where it connects to the torch. Your idea makes more sense than any I have come up with.  Do you suppose it is safe to use the way it is?
Reply:Originally Posted by mdepotWe recently purchased a torch kit from Harbor Freight....  Any ideas?