Off Color choke lever issues

Okay, I need some input from the guys who have ha dealings with Cub Cadets.  I just got done splitting and reassembling my Cub Cadet 1650 last week.  It went as well as expected, which is to say I don't really want to do it again.  We've been trying to tune the carberator with marginal success.  we get it tuned, put the air cleaner back on and it's not the same.  That's probably because of the bad air filter that I should have picked up last week when I got parts.  As it stands now the choke button won't stay pushed in when you run the engine.  It will push all the way in but as the motor runs it slides back out about a quarter of an inch or so.  I have to hold it in for the engine to run decent.  We've adjusted the cable at either end with no effect.  We've kind of decided that the choke lever is moving regardless of adjustment.  Probably from wear?  What do I need to do to fix this?  I just don't have enough hands to steer, run the hydro lever, and hold the choke in all at once.