Cmp, my guess is one of three things is causing your problem. First, it could be that the nut holding the record to the platter is not quite tight enough, as Rwd suggests.
Second, and likely if not the first reason, the adjustable collet on the vacuum post is set too high on the post and, combined with a strong vacuum, the wand is pulled down too hard on the record surface. Do a dry run by swinging the wand over the record and turning on the vacuum with the motor running. The wand should come down flat against the record and JUST enough to provide solid suction contact. Lifting the wand with one hand as you shut off the vaccum will let you decide if you are getting good suction. If needed, loosen the allen set screw and adjust the collet height.
Third, though not likely. is that your motor shaft/bearings are worn out. Unless it is VERY old or has been abused, mine is 15 years old, I doubt this is the case.
One last thing is that the 16.5, unless you have installed a motor fan, will only do bout 6 LP's before the motor gets hot. When it gets too hiot, it willshut down and the platter won't turn. After cooloing, it will work fine again.
