Theoban eliminator help needed

[Shed tuner]

Thank for your reply, real strong cooking pressure, and a lot of recoil, so hopefully it is as you say, and hopefully I can get the right size O rings for it. Just have to attempt to strip it down now.
Thanks

depressurise the ram.. remove stock, removing valve cover screw in rear, small punch and very gentle taps on the valve stem with a hammer to get the air to bleed out in small, sharp blasts. Lots of small taps is the way to go...