I just cleaned my source (5977B Extractor source) using the documented Agilent method (Alumina, DIW, Methanol, Hexanes-no acetone step our lab does not have LCMS grade acetone so I skipped it). I spent a lot of time carefully cleaning the repeller (no circular motions, only back and forth on the bottom surface etc.)
The voltage had been hovering around 30-35V for a while and it's been about 6 months since we have cleaned the source (we have a very clean matrix so it's not a huge issue). I was under the assumption that the repeller voltage should drop after a cleaning.