Just got a used Bosch 1617 ESV off ebay. I've been checking every thing out and there seem s to be an issue with the fine adjustment. It is binding at about the middle of the adjustment range. Is this a problem with this Bosch model in general or do you think there's something wrong with this particular unit? I did take the motor out of the base and checked the adjustment threads. There did not appear to be saw dust or chips causing the problem. Maybe I'm not seating the motor properly in the base? Need some help so I can decide to keep it or send it back.