gas regulator leaking gas

[kelmen]

i connected this gas regulator to the gas tank, and found pressure leaking

from some other feedback, i believe it can be resolved by applying o-ring rubber
however this regulator connector has no placeholder for the rubber ring

is it diy-able to attach the ring onto it? or i need to get the proper regulator

 

[acidrain]

What gas? Does that reg fit the tank? Obviously, that reg uses a brass seat, and is not designed for an o-ring. Most smaller co2 tanks use a flat face & plastic/fiber gasket. Larger welding tanks use that style of reg, but they are high pressure gas, not liquefied co2.
If the reg fits the tank, and you are having a gas leak other than the reg itself, it could simply be the tank valve.
Tank valves are designed to be fully opened hard to the stop. If you are not fully opening the tank valve, it will leak at the valve stem.
High pressure leaks are extremely hard to locate, even with soapy water. The high pressure jet of gas will blow the soapy water away and not bubble like a lower pressure leak will.
Sometimes the only way to really see the leak is to fully submerge the whole set up in water.