« on: January 30, 2016, 10:53:07 AM »
Just to reiterate, the threads on the O2 tank are left hand, so, as noted earlier, turn the regulator body to the right to loosen it.
Also as noted, sometimes the tank threads need a little lubrication. The current red tank I have needed it. I found that I could get the regulator on but getting it off the tank was very difficult. I used keg lube since that was what I had handy, but any food grade lubricant will work.
I take the regulator off each time, since I've found that leaving it on the tank results in an empty tank.