If you are burning oil, your rings are toast, not your valves....although, they could also be bad.
An engine puts out a lot of moisture whether it is good or bad. Most of it evaporates in the exhaust system.
What screw are you turning to adjust mixture.............sounds to me like you are turning the idle screw or the choke adjustment screw.
Also, sounds to me like you should study up on how an engine works...............