If the acetyline cylinder has been lying on it's side it will be knackered. Also I would remove the flame arresters if possible, strip them down and soak in vinegar. All threads and connections should be exammined for damage. There are also non retun valves in the torch tthese should be looked at. As said flex the hoses and if any sign of cracking on the outer rubber / covering replace. Finally if you are satisfied that all is in order, slowly open the O2 bottle and in a well ventilated area purge through the line upto and including the torch. When satisfied with that do either but preferably both shut the O2 valve on the bottle and torch and observe if there is any pressure drop, all so though it is a good idea to do a soapy water test around all connections. Repeat the same procedure for the acetyline.
UNDER NO circumstances be tempted touse any oil or grease based products on any threaded sections of the gas bottles or gas regulators.