What's wrong with my VPI motor?

I have a VPI HW-19 Mk4 turntable that sometimes experiences the same symptoms you describe. Assuming there is nothing wrong with the motor, I suspect that the drive belt is slipping. The VPI drive belt needs to be periodically dusted with talcum powder so there is some friction between the belt and the perimeter of the platter. Simply put a little baby talc in a ziplock bag, toss in the drive belt, shake it, then remove the belt and knock off the excess talc, and reinstall the belt.

does the motor vibrate and not turn? the switch may be at fault. BUT, when i got the SDS i had to "crank up the voltage" (the old plc-2 i had worked great!)
to get the motor to start. but when i plugged the motor directly into the wall it worked flawlessly. vpi sent me a resistor/capacitor or something for free IF i wanted to dis-assemble the (huge)
motor, but i decided to go with the "noisier" start up voltage instead (84V?). definitely get some talc and treat the belt 1st. then e-mail vpi- they're pretty nice about addressing these quirky problems.

Thanks all...I will check it out tonight!

Just a thought, but the motor shaft itself needs occasional lubrication. Just talked to Mike at VPI about this, re my older model TNT, and he recommended using 40 weight oil VERY SPARINGLY, via one of those needle-applicators, beng sure you don't get any oil on the pulley.

Also, for some time the pulley does occasionally seem to "lock up" and not turn without a gentle push, especially since I got my SDS. But the push always gets it going. At least so far. Good luck, Dave

One other thing to note. Make sure that there isn't extra talc stuck in the motor spindle groove. My belt was riding up and down the plattyer, like there was a turn or a kink in it. I found this extra talc, picked it out with a toothpick, cleaned it and the platter edge with some Windex and all was fixed.

Enjoy,
Bob