Hello.. There is no way ...other than pressure testing and using a "leak detecting fluid" ( you can use "Windex" in a pinch )to ascertain where the "leak" is ... if you are not using a gauge on your setup ( see pic in # 20) As i have previously stated with pressure on the cylinder and pressing on something ...i have no discernible leaking ( overnight tests with valve center position .."Off")..I have not tried to "press sideways" on the cylinder rod. ( also i have a different cylinder) Make sure that you have the "Valve" connected correctly .... the "P" is the pressure input, A & B are outputs...If you connect it some other way ...it will leak. If everything is OK there should be no air leaks.... Regards Fred
PS: If you have enough air capacity ( your tank) loosing a few pounds of pressure won't be a problem, as the regulator will adjust for this anyway.