[Healeys] overdrive problem

[healeymanjim]

changed a leaking gasket on side of BT7 o/d.  also replaced synthetic oil with 30ND.  now cannot get o/d to engage.  
solenoid worked fine on static check but would not engage o/d while driving.  ordered new solenoid and same situation.  
started out with book instructions, no luck.  tried other positions and will not engage.  if i push a little on right side arm it 
engages immedietely.  again, it was working fine before we changed the gasket on the side plate and replaced o rings on 
both sides of shaft.  one thing i did notice was that o-ring on pax side was flat and replacement was round.  the solenoid 
does not seem to be able to lift the arm while moving, but will when checking it while stopped. any ideas?