Comment laurell-R SNF 2011-02-17 12:30:39: there seems to be a small leak in O ring top

[lindaw at snf.stanford.edu]

There seems to be a small air leak past the top cover O ring near the screw at 8 O'clock,  Just to the upper left of the screw.  
Dribbled a bit of acetone on the outside and saw it get sucked into the bowl.  This is similar to the problem I had earlier this year with non uniform spins, and was fixed at that time.  Perhaps this screw has loosened?